Merge Chromium at r10.0.634.0: Initial merge by git.

Change-Id: Iac2af492818d119bcc2562eb5fdabf5ab0b6df9c

71 files changed, 3040 insertions, 1373 deletions

diff --git a/chrome/browser/sync/abstract_profile_sync_service_test.h b/chrome/browser/sync/abstract_profile_sync_service_test.h
index 57b3791..b5fc1c2 100644
--- a/chrome/browser/sync/abstract_profile_sync_service_test.h
+++ b/chrome/browser/sync/abstract_profile_sync_service_test.h
@@ -15,6 +15,7 @@
 #include "chrome/browser/net/gaia/token_service.h"
 #include "chrome/browser/sync/engine/syncapi.h"
 #include "chrome/browser/sync/glue/autofill_model_associator.h"
+#include "chrome/browser/sync/glue/autofill_profile_model_associator.h"
 #include "chrome/browser/sync/glue/password_model_associator.h"
 #include "chrome/browser/sync/glue/preference_model_associator.h"
 #include "chrome/browser/sync/glue/session_model_associator.h"
@@ -65,6 +66,9 @@ class ProfileSyncServiceTestHelper {
       case syncable::AUTOFILL:
         tag_name = browser_sync::kAutofillTag;
         break;
+      case syncable::AUTOFILL_PROFILE:
+        tag_name = browser_sync::kAutofillProfileTag;
+        break;
       case syncable::PREFERENCES:
         tag_name = browser_sync::kPreferencesTag;
         break;
diff --git a/chrome/browser/sync/engine/read_node_mock.h b/chrome/browser/sync/engine/read_node_mock.h
index f13eddd..564f01d 100644
--- a/chrome/browser/sync/engine/read_node_mock.h
+++ b/chrome/browser/sync/engine/read_node_mock.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.

+// Copyright (c) 2011 The Chromium Authors. All rights reserved.

 // Use of this source code is governed by a BSD-style license that can be

 // found in the LICENSE file.

 

@@ -13,8 +13,9 @@
 

 class ReadNodeMock : public sync_api::ReadNode {

  public:

-  ReadNodeMock()  { }

+  ReadNodeMock() {}

   virtual ~ReadNodeMock() {}

+

   MOCK_METHOD2(InitByClientTagLookup,

                bool(syncable::ModelType model_type, const std::string& tag));

   MOCK_CONST_METHOD0(GetAutofillProfileSpecifics,

@@ -25,5 +26,6 @@ class ReadNodeMock : public sync_api::ReadNode {
   MOCK_CONST_METHOD0(GetSuccessorId, int64());

   MOCK_METHOD1(InitByIdLookup, bool(int64 id));

 };

+

 #endif  // CHROME_BROWSER_SYNC_ENGINE_READ_NODE_MOCK_H_

 

diff --git a/chrome/browser/sync/engine/syncapi.cc b/chrome/browser/sync/engine/syncapi.cc
index 112878d..206125b 100644
--- a/chrome/browser/sync/engine/syncapi.cc
+++ b/chrome/browser/sync/engine/syncapi.cc
@@ -14,7 +14,6 @@
 #include "base/lock.h"
 #include "base/logging.h"
 #include "base/message_loop.h"
-#include "base/platform_thread.h"
 #include "base/scoped_ptr.h"
 #include "base/sha1.h"
 #include "base/string_util.h"
@@ -217,6 +216,10 @@ int64 BaseNode::GetId() const {
   return GetEntry()->Get(syncable::META_HANDLE);
 }
 
+int64 BaseNode::GetModificationTime() const {
+  return GetEntry()->Get(syncable::MTIME);
+}
+
 bool BaseNode::GetIsFolder() const {
   return GetEntry()->Get(syncable::IS_DIR);
 }
diff --git a/chrome/browser/sync/engine/syncapi.h b/chrome/browser/sync/engine/syncapi.h
index e2503cb..d86ed71 100644
--- a/chrome/browser/sync/engine/syncapi.h
+++ b/chrome/browser/sync/engine/syncapi.h
@@ -153,6 +153,9 @@ class BaseNode {
   // different ID value.
   virtual int64 GetId() const;
 
+  // Returns the modification time of the object (in TimeTicks internal format).
+  int64 GetModificationTime() const;
+
   // Nodes are hierarchically arranged into a single-rooted tree.
   // InitByRootLookup on ReadNode allows access to the root. GetParentId is
   // how you find a node's parent.
diff --git a/chrome/browser/sync/engine/syncer_thread.cc b/chrome/browser/sync/engine/syncer_thread.cc
index 501577d..3c0cd06 100644
--- a/chrome/browser/sync/engine/syncer_thread.cc
+++ b/chrome/browser/sync/engine/syncer_thread.cc
@@ -59,7 +59,7 @@ void SyncerThread::NudgeSyncerWithDataTypes(
     int milliseconds_from_now,
     NudgeSource source,
     const syncable::ModelTypeBitSet& model_types) {
-  AutoLock lock(lock_);
+  base::AutoLock lock(lock_);
   if (vault_.syncer_ == NULL) {
     return;
   }
@@ -70,7 +70,7 @@ void SyncerThread::NudgeSyncerWithDataTypes(
 void SyncerThread::NudgeSyncer(
     int milliseconds_from_now,
     NudgeSource source) {
-  AutoLock lock(lock_);
+  base::AutoLock lock(lock_);
   if (vault_.syncer_ == NULL) {
     return;
   }
@@ -107,7 +107,7 @@ SyncerThread::~SyncerThread() {
 // and false otherwise.
 bool SyncerThread::Start() {
   {
-    AutoLock lock(lock_);
+    base::AutoLock lock(lock_);
     if (thread_.IsRunning()) {
       return true;
     }
@@ -141,7 +141,7 @@ bool SyncerThread::Stop(int max_wait) {
 
 void SyncerThread::RequestSyncerExitAndSetThreadStopConditions() {
   {
-    AutoLock lock(lock_);
+    base::AutoLock lock(lock_);
     // If the thread has been started, then we either already have or are about
     // to enter ThreadMainLoop so we have to proceed with shutdown and wait for
     // it to finish.  If the thread has not been started --and we now own the
@@ -170,7 +170,7 @@ void SyncerThread::RequestSyncerExitAndSetThreadStopConditions() {
 }
 
 bool SyncerThread::RequestPause() {
-  AutoLock lock(lock_);
+  base::AutoLock lock(lock_);
   if (vault_.pause_requested_ || vault_.paused_)
     return false;
 
@@ -195,7 +195,7 @@ void SyncerThread::Notify(SyncEngineEvent::EventCause cause) {
 }
 
 bool SyncerThread::RequestResume() {
-  AutoLock lock(lock_);
+  base::AutoLock lock(lock_);
   // Only valid to request a resume when we are already paused or we
   // have a pause pending.
   if (!(vault_.paused_ || vault_.pause_requested_))
@@ -530,7 +530,7 @@ SyncerThread::WaitInterval SyncerThread::CalculatePollingWaitTime(
 }
 
 void SyncerThread::ThreadMain() {
-  AutoLock lock(lock_);
+  base::AutoLock lock(lock_);
   // Signal Start() to let it know we've made it safely onto the message loop,
   // and unblock it's caller.
   thread_main_started_.Signal();
@@ -637,7 +637,7 @@ SyncSourceInfo SyncerThread::MakeSyncSourceInfo(bool nudged,
 }
 
 void SyncerThread::CreateSyncer(const std::string& dirname) {
-  AutoLock lock(lock_);
+  base::AutoLock lock(lock_);
   VLOG(1) << "Creating syncer up for: " << dirname;
   // The underlying database structure is ready, and we should create
   // the syncer.
@@ -655,7 +655,7 @@ void SyncerThread::CreateSyncer(const std::string& dirname) {
 // server.
 static inline void CheckConnected(bool* connected,
                                   HttpResponse::ServerConnectionCode code,
-                                  ConditionVariable* condvar) {
+                                  base::ConditionVariable* condvar) {
   if (*connected) {
     // Note, be careful when adding cases here because if the SyncerThread
     // thinks there is no valid connection as determined by this method, it
@@ -686,7 +686,7 @@ void SyncerThread::WatchConnectionManager(ServerConnectionManager* conn_mgr) {
 void SyncerThread::HandleServerConnectionEvent(
     const ServerConnectionEvent& event) {
   if (ServerConnectionEvent::STATUS_CHANGED == event.what_happened) {
-    AutoLock lock(lock_);
+    base::AutoLock lock(lock_);
     CheckConnected(&vault_.connected_, event.connection_code,
                    &vault_field_changed_);
   }
@@ -771,7 +771,7 @@ void SyncerThread::NudgeSyncImpl(int milliseconds_from_now,
 }
 
 void SyncerThread::SetNotificationsEnabled(bool notifications_enabled) {
-  AutoLock lock(lock_);
+  base::AutoLock lock(lock_);
   session_context_->set_notifications_enabled(notifications_enabled);
 }
 
diff --git a/chrome/browser/sync/engine/syncer_thread.h b/chrome/browser/sync/engine/syncer_thread.h
index 6681225..22531d8 100644
--- a/chrome/browser/sync/engine/syncer_thread.h
+++ b/chrome/browser/sync/engine/syncer_thread.h
@@ -14,21 +14,22 @@
 #include <vector>
 
 #include "base/basictypes.h"
-#include "base/condition_variable.h"
 #include "base/gtest_prod_util.h"
 #include "base/ref_counted.h"
 #include "base/scoped_ptr.h"
-#include "base/thread.h"
+#include "base/synchronization/condition_variable.h"
+#include "base/threading/thread.h"
 #include "base/time.h"
-#include "base/waitable_event.h"
-#if defined(OS_LINUX)
-#include "chrome/browser/sync/engine/idle_query_linux.h"
-#endif
+#include "base/synchronization/waitable_event.h"
 #include "chrome/browser/sync/engine/syncer_types.h"
 #include "chrome/browser/sync/sessions/sync_session.h"
 #include "chrome/browser/sync/syncable/model_type.h"
 #include "chrome/common/deprecated/event_sys-inl.h"
 
+#if defined(OS_LINUX)
+#include "chrome/browser/sync/engine/idle_query_linux.h"
+#endif
+
 class EventListenerHookup;
 
 namespace browser_sync {
@@ -213,10 +214,10 @@ class SyncerThread : public base::RefCountedThreadSafe<SyncerThread>,
 
   // Gets signaled whenever a thread outside of the syncer thread changes a
   // protected field in the vault_.
-  ConditionVariable vault_field_changed_;
+  base::ConditionVariable vault_field_changed_;
 
   // Used to lock everything in |vault_|.
-  Lock lock_;
+  base::Lock lock_;
 
  private:
   // Threshold multipler for how long before user should be considered idle.
diff --git a/chrome/browser/sync/engine/syncer_thread_unittest.cc b/chrome/browser/sync/engine/syncer_thread_unittest.cc
index 887bcc1..df0733b 100644
--- a/chrome/browser/sync/engine/syncer_thread_unittest.cc
+++ b/chrome/browser/sync/engine/syncer_thread_unittest.cc
@@ -8,7 +8,7 @@
 #include "base/lock.h"
 #include "base/scoped_ptr.h"
 #include "base/time.h"
-#include "base/waitable_event.h"
+#include "base/synchronization/waitable_event.h"
 #include "chrome/browser/sync/engine/model_safe_worker.h"
 #include "chrome/browser/sync/engine/syncer_thread.h"
 #include "chrome/browser/sync/engine/syncer_types.h"
diff --git a/chrome/browser/sync/glue/autofill_data_type_controller.h b/chrome/browser/sync/glue/autofill_data_type_controller.h
index d73edf2..2daedb4 100644
--- a/chrome/browser/sync/glue/autofill_data_type_controller.h
+++ b/chrome/browser/sync/glue/autofill_data_type_controller.h
@@ -10,7 +10,7 @@
 
 #include "base/basictypes.h"
 #include "base/scoped_ptr.h"
-#include "base/waitable_event.h"
+#include "base/synchronization/waitable_event.h"
 #include "chrome/browser/autofill/personal_data_manager.h"
 #include "chrome/browser/sync/profile_sync_factory.h"
 #include "chrome/browser/sync/profile_sync_service.h"
diff --git a/chrome/browser/sync/glue/autofill_data_type_controller_unittest.cc b/chrome/browser/sync/glue/autofill_data_type_controller_unittest.cc
index 6ff8af6..127b591 100644
--- a/chrome/browser/sync/glue/autofill_data_type_controller_unittest.cc
+++ b/chrome/browser/sync/glue/autofill_data_type_controller_unittest.cc
@@ -8,7 +8,7 @@
 #include "base/message_loop.h"
 #include "base/ref_counted.h"
 #include "base/scoped_ptr.h"
-#include "base/waitable_event.h"
+#include "base/synchronization/waitable_event.h"
 #include "chrome/browser/autofill/personal_data_manager.h"
 #include "chrome/browser/browser_thread.h"
 #include "chrome/browser/sync/glue/autofill_data_type_controller.h"
diff --git a/chrome/browser/sync/glue/autofill_model_associator.cc b/chrome/browser/sync/glue/autofill_model_associator.cc
index f1340df..289d5fb 100644
--- a/chrome/browser/sync/glue/autofill_model_associator.cc
+++ b/chrome/browser/sync/glue/autofill_model_associator.cc
@@ -237,8 +237,7 @@ bool AutofillModelAssociator::TraverseAndAssociateAllSyncNodes(
 
   bool autofill_profile_not_migrated = HasNotMigratedYet(write_trans);
 
-  if (MigrationLoggingEnabled() &&
-     autofill_profile_not_migrated) {
+  if (VLOG_IS_ON(1) && autofill_profile_not_migrated) {
     VLOG(1) << "[AUTOFILL MIGRATION]"
             << "Printing profiles from web db";
 
@@ -251,7 +250,7 @@ bool AutofillModelAssociator::TraverseAndAssociateAllSyncNodes(
     }
   }
 
-  if (MigrationLoggingEnabled() && autofill_profile_not_migrated) {
+  if (autofill_profile_not_migrated) {
     VLOG(1) << "[AUTOFILL MIGRATION]"
             << "Iterating over sync db";
   }
@@ -271,11 +270,9 @@ bool AutofillModelAssociator::TraverseAndAssociateAllSyncNodes(
     } else if (autofill.has_profile()) {
       // Ignore autofill profiles if we are not upgrading.
       if (autofill_profile_not_migrated) {
-        if (MigrationLoggingEnabled()) {
-          VLOG(1) << "[AUTOFILL MIGRATION] Looking for "
-                  << autofill.profile().name_first()
-                  << autofill.profile().name_last();
-        }
+        VLOG(1) << "[AUTOFILL MIGRATION] Looking for "
+                << autofill.profile().name_first()
+                << autofill.profile().name_last();
         AddNativeProfileIfNeeded(
             autofill.profile(),
             bundle,
@@ -355,19 +352,15 @@ void AutofillModelAssociator::AddNativeProfileIfNeeded(
       profile, all_profiles_from_db);
 
   if (profile_in_web_db != NULL) {
-    if (MigrationLoggingEnabled()) {
-      VLOG(1) << "[AUTOFILL MIGRATION]"
-              << "Node found in web db. So associating";
-    }
+    VLOG(1) << "[AUTOFILL MIGRATION]"
+            << "Node found in web db. So associating";
     int64 sync_id = node.GetId();
     std::string guid = profile_in_web_db->guid();
     Associate(&guid, sync_id);
     return;
   } else {  // Create a new node.
-    if (MigrationLoggingEnabled()) {
-      VLOG(1) << "[AUTOFILL MIGRATION]"
-              << "Node not found in web db so creating and associating";
-    }
+    VLOG(1) << "[AUTOFILL MIGRATION]"
+            << "Node not found in web db so creating and associating";
     std::string guid = guid::GenerateGUID();
     Associate(&guid, node.GetId());
     AutoFillProfile* p = new AutoFillProfile(guid);
@@ -555,11 +548,9 @@ bool AutofillModelAssociator::HasNotMigratedYet(
   }
 
   if (autofill_migration_state == syncable::INSUFFICIENT_INFO_TO_DETERMINE) {
-      if (MigrationLoggingEnabled()) {
-        VLOG(1) << "[AUTOFILL MIGRATION]"
-                << "current autofill migration state is insufficient info to"
-                << "determine.";
-      }
+      VLOG(1) << "[AUTOFILL MIGRATION]"
+              << "current autofill migration state is insufficient info to"
+              << "determine.";
       sync_api::ReadNode autofill_profile_root_node(trans);
       if (!autofill_profile_root_node.InitByTagLookup(
           browser_sync::kAutofillProfileTag) ||
@@ -568,29 +559,21 @@ bool AutofillModelAssociator::HasNotMigratedYet(
         sync_service()->backend()->SetAutofillMigrationState(
             syncable::NOT_MIGRATED);
 
-        if (MigrationLoggingEnabled()) {
-          VLOG(1) << "[AUTOFILL MIGRATION]"
-                  << "Current autofill migration state is NOT Migrated because"
-                  << "legacy autofill root node is present whereas new "
-                  << "Autofill profile root node is absent.";
-        }
+        VLOG(1) << "[AUTOFILL MIGRATION]"
+                << "Current autofill migration state is NOT Migrated because"
+                << "legacy autofill root node is present whereas new "
+                << "Autofill profile root node is absent.";
         return true;
       }
 
       sync_service()->backend()->SetAutofillMigrationState(syncable::MIGRATED);
 
-      if (MigrationLoggingEnabled()) {
-          VLOG(1) << "[AUTOFILL MIGRATION]"
-                  << "Current autofill migration state is migrated.";
-      }
+      VLOG(1) << "[AUTOFILL MIGRATION]"
+              << "Current autofill migration state is migrated.";
   }
 
   return false;
 }
 
-bool AutofillModelAssociator::MigrationLoggingEnabled() {
-  // [TODO] enable logging via a command line flag.
-  return false;
-}
 }  // namespace browser_sync
 
diff --git a/chrome/browser/sync/glue/autofill_model_associator.h b/chrome/browser/sync/glue/autofill_model_associator.h
index 3f1104e..553580f 100644
--- a/chrome/browser/sync/glue/autofill_model_associator.h
+++ b/chrome/browser/sync/glue/autofill_model_associator.h
@@ -173,8 +173,6 @@ class AutofillModelAssociator
   // user requested an abort.
   bool IsAbortPending();
 
-  bool MigrationLoggingEnabled();
-
   ProfileSyncService* sync_service_;
   WebDatabase* web_database_;
   PersonalDataManager* personal_data_;
diff --git a/chrome/browser/sync/glue/autofill_profile_model_associator.cc b/chrome/browser/sync/glue/autofill_profile_model_associator.cc
index b2d2e2c..c517e2c 100644
--- a/chrome/browser/sync/glue/autofill_profile_model_associator.cc
+++ b/chrome/browser/sync/glue/autofill_profile_model_associator.cc
@@ -46,7 +46,7 @@ bool AutofillProfileModelAssociator::TraverseAndAssociateChromeAutoFillProfiles(
     std::vector<AutoFillProfile*>* new_profiles,
     std::vector<std::string>* profiles_to_delete) {
 
-  if (MigrationLoggingEnabled()) {
+  if (VLOG_IS_ON(1)) {
     VLOG(1) << "[AUTOFILL MIGRATION]"
             << "Printing profiles from web db";
 
@@ -60,10 +60,9 @@ bool AutofillProfileModelAssociator::TraverseAndAssociateChromeAutoFillProfiles(
     }
   }
 
-  if (MigrationLoggingEnabled()) {
-    VLOG(1) << "[AUTOFILL MIGRATION]"
-            << "Looking for the above data in sync db..";
-  }
+  VLOG(1) << "[AUTOFILL MIGRATION]"
+          << "Looking for the above data in sync db..";
+
   // Alias the all_profiles_from_db so we fit in 80 characters
   const std::vector<AutoFillProfile*>& profiles(all_profiles_from_db);
   for (std::vector<AutoFillProfile*>::const_iterator ix = profiles.begin();
@@ -72,15 +71,18 @@ bool AutofillProfileModelAssociator::TraverseAndAssociateChromeAutoFillProfiles(
     std::string guid((*ix)->guid());
 
     ReadNode node(write_trans);
-    if (node.InitByClientTagLookup(syncable::AUTOFILL_PROFILE, guid)) {
-      if (MigrationLoggingEnabled()) {
-        VLOG(1) << "[AUTOFILL MIGRATION]"
-                << " Found in sync db: "
-                << (*ix)->GetFieldText(AutoFillType(NAME_FIRST))
-                << (*ix)->GetFieldText(AutoFillType(NAME_LAST))
-                << (*ix)->guid()
-                << " so associating";
-      }
+    if (node.InitByClientTagLookup(syncable::AUTOFILL_PROFILE, guid) &&
+        // The following check is to ensure the given sync node is not already
+        // associated with another profile. That could happen if the user has
+        // the same profile duplicated.
+        current_profiles->find(guid) == current_profiles->end()) {
+
+      VLOG(1) << "[AUTOFILL MIGRATION]"
+              << " Found in sync db: "
+              << (*ix)->GetFieldText(AutoFillType(NAME_FIRST))
+              << (*ix)->GetFieldText(AutoFillType(NAME_LAST))
+              << (*ix)->guid()
+              << " so associating with node id " << node.GetId();
       const sync_pb::AutofillProfileSpecifics& autofill(
           node.GetAutofillProfileSpecifics());
       if (OverwriteProfileWithServerData(*ix, autofill)) {
@@ -138,11 +140,9 @@ bool AutofillProfileModelAssociator::AssociateModels() {
     return false;
   }
 
-  if (MigrationLoggingEnabled()) {
-    VLOG(1) << "[AUTOFILL MIGRATION]"
-            << " Now associating to the new autofill profile model associator"
-            << " root node";
-  }
+  VLOG(1) << "[AUTOFILL MIGRATION]"
+          << " Now associating to the new autofill profile model associator"
+          << " root node";
   DataBundle bundle;
   {
     // The write transaction lock is held inside this block.
@@ -251,7 +251,8 @@ bool AutofillProfileModelAssociator::OverwriteProfileWithServerData(
 int64 AutofillProfileModelAssociator::FindSyncNodeWithProfile(
     sync_api::WriteTransaction* trans,
     const sync_api::BaseNode& autofill_root,
-    const AutoFillProfile& profile_from_db) {
+    const AutoFillProfile& profile_from_db,
+    std::set<std::string>* current_profiles) {
   int64 sync_child_id = autofill_root.GetFirstChildId();
   while (sync_child_id != sync_api::kInvalidId) {
     ReadNode read_node(trans);
@@ -263,9 +264,14 @@ int64 AutofillProfileModelAssociator::FindSyncNodeWithProfile(
     }
     const sync_pb::AutofillProfileSpecifics& autofill_specifics(
         read_node.GetAutofillProfileSpecifics());
-    OverwriteProfileWithServerData(&p, autofill_specifics);
-    if (p.Compare(profile_from_db) == 0) {
-      return sync_child_id;
+
+    // This find should be fast as the set uses tree.
+    if (current_profiles->find(autofill_specifics.guid())
+        == current_profiles->end()) {
+      OverwriteProfileWithServerData(&p, autofill_specifics);
+      if (p.Compare(profile_from_db) == 0) {
+        return sync_child_id;
+      }
     }
     sync_child_id = read_node.GetSuccessorId();
   }
@@ -280,7 +286,10 @@ bool AutofillProfileModelAssociator::MakeNewAutofillProfileSyncNodeIfNeeded(
     std::set<std::string>* current_profiles,
     std::vector<std::string>* profiles_to_delete) {
 
-  int64 sync_node_id = FindSyncNodeWithProfile(trans, autofill_root, profile);
+  int64 sync_node_id = FindSyncNodeWithProfile(trans,
+      autofill_root,
+      profile,
+      current_profiles);
   if (sync_node_id != sync_api::kInvalidId) {
     // In case of duplicates throw away the local profile and apply the
     // server profile.(The only difference between the 2 profiles are the guids)
@@ -298,14 +307,13 @@ bool AutofillProfileModelAssociator::MakeNewAutofillProfileSyncNodeIfNeeded(
     std::string guid = autofill_specifics.guid();
     Associate(&guid, sync_node_id);
     current_profiles->insert(autofill_specifics.guid());
-    if (MigrationLoggingEnabled()) {
-      VLOG(1) << "[AUTOFILL MIGRATION]"
-              << "Found in sync db but with a different guid: "
-              << UTF16ToUTF8(profile.GetFieldText(AutoFillType(NAME_FIRST)))
-              << UTF16ToUTF8(profile.GetFieldText(AutoFillType(NAME_LAST)))
-              << "New guid " << autofill_specifics.guid()
-              << " so associating";
-    }
+    VLOG(1) << "[AUTOFILL MIGRATION]"
+            << "Found in sync db but with a different guid: "
+            << UTF16ToUTF8(profile.GetFieldText(AutoFillType(NAME_FIRST)))
+            << UTF16ToUTF8(profile.GetFieldText(AutoFillType(NAME_LAST)))
+            << "New guid " << autofill_specifics.guid() << " sync node id "
+            << sync_node_id << " so associating. Profile to be deleted "
+            << profile.guid();
   } else {
     sync_api::WriteNode node(trans);
     if (!node.InitUniqueByCreation(
@@ -314,16 +322,17 @@ bool AutofillProfileModelAssociator::MakeNewAutofillProfileSyncNodeIfNeeded(
       return false;
     }
     node.SetTitle(UTF8ToWide(profile.guid()));
-    if (MigrationLoggingEnabled()) {
-      VLOG(1) << "[AUTOFILL MIGRATION]"
-              << "NOT Found in sync db  "
-              << UTF16ToUTF8(profile.GetFieldText(AutoFillType(NAME_FIRST)))
-              << UTF16ToUTF8(profile.GetFieldText(AutoFillType(NAME_LAST)))
-              << profile.guid()
-              << " so creating a new sync node.";
-    }
+    VLOG(1) << "[AUTOFILL MIGRATION]"
+            << "NOT Found in sync db  "
+            << UTF16ToUTF8(profile.GetFieldText(AutoFillType(NAME_FIRST)))
+            << UTF16ToUTF8(profile.GetFieldText(AutoFillType(NAME_LAST)))
+            << profile.guid()
+            << " so creating a new sync node. Sync node id "
+            << node.GetId();
     AutofillProfileChangeProcessor::WriteAutofillProfile(profile, &node);
     current_profiles->insert(profile.guid());
+    std::string guid = profile.guid();
+    Associate(&guid, node.GetId());
     number_of_profiles_created_++;
 
   }
@@ -335,11 +344,9 @@ bool AutofillProfileModelAssociator::TraverseAndAssociateAllSyncNodes(
     const sync_api::ReadNode& autofill_root,
     DataBundle* bundle) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::DB));
+  VLOG(1) << "[AUTOFILL MIGRATION] "
+          << " Iterating over sync nodes of autofill profile root node";
 
-  if (MigrationLoggingEnabled()) {
-    VLOG(1) << "[AUTOFILL MIGRATION] "
-            << " Iterating over sync nodes of autofill profile root node";
-  }
   int64 sync_child_id = autofill_root.GetFirstChildId();
   while (sync_child_id != sync_api::kInvalidId) {
     ReadNode sync_child(write_trans);
@@ -363,14 +370,15 @@ void AutofillProfileModelAssociator::AddNativeProfileIfNeeded(
     const sync_api::ReadNode& node) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::DB));
 
-  if (MigrationLoggingEnabled()) {
-    VLOG(1) << "[AUTOFILL MIGRATION] "
-            << "Trying to lookup "
-            << profile.name_first()
-            << " "
-            << profile.name_last()
-            << " in the web db";
-  }
+  VLOG(1) << "[AUTOFILL MIGRATION] "
+          << "Trying to lookup "
+          << profile.name_first()
+          << " "
+          << profile.name_last()
+          << "sync node id " << node.GetId()
+          << " Guid " << profile.guid()
+          << " in the web db";
+
   if (bundle->current_profiles.find(profile.guid()) ==
       bundle->current_profiles.end()) {
     std::string guid(profile.guid());
@@ -378,15 +386,11 @@ void AutofillProfileModelAssociator::AddNativeProfileIfNeeded(
     AutoFillProfile* p = new AutoFillProfile(profile.guid());
     OverwriteProfileWithServerData(p, profile);
     bundle->new_profiles.push_back(p);
-    if (MigrationLoggingEnabled()) {
-      VLOG(1) << "[AUTOFILL MIGRATION] "
-              << " Did not find one so creating it on web db";
-    }
+    VLOG(1) << "[AUTOFILL MIGRATION] "
+            << " Did not find one so creating it on web db";
   } else {
-    if (MigrationLoggingEnabled()) {
-      VLOG(1) << "[AUTOFILL MIGRATION] "
-              << " Found it on web db. Moving on ";
-    }
+    VLOG(1) << "[AUTOFILL MIGRATION] "
+            << " Found it on web db. Moving on ";
   }
 }
 
@@ -469,10 +473,5 @@ bool AutofillProfileModelAssociator::IsAbortPending() {
   return abort_association_pending_;
 }
 
-bool AutofillProfileModelAssociator::MigrationLoggingEnabled() {
-  // TODO(lipalani) enable logging via a command line flag.
-  return false;
-}
-
 }  // namespace browser_sync
 
diff --git a/chrome/browser/sync/glue/autofill_profile_model_associator.h b/chrome/browser/sync/glue/autofill_profile_model_associator.h
index f636b63..e2abdaf 100644
--- a/chrome/browser/sync/glue/autofill_profile_model_associator.h
+++ b/chrome/browser/sync/glue/autofill_profile_model_associator.h
@@ -161,9 +161,8 @@ class AutofillProfileModelAssociator
 
   int64 FindSyncNodeWithProfile(sync_api::WriteTransaction* trans,
       const sync_api::BaseNode& autofill_root,
-      const AutoFillProfile& profile);
-
-  bool MigrationLoggingEnabled();
+      const AutoFillProfile& profile,
+      std::set<std::string>* current_profiles);
 
   ProfileSyncService* sync_service_;
   WebDatabase* web_database_;
diff --git a/chrome/browser/sync/glue/change_processor_mock.cc b/chrome/browser/sync/glue/change_processor_mock.cc
new file mode 100644
index 0000000..faea86b
--- /dev/null
+++ b/chrome/browser/sync/glue/change_processor_mock.cc
@@ -0,0 +1,13 @@
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chrome/browser/sync/glue/change_processor_mock.h"
+
+namespace browser_sync {
+
+ChangeProcessorMock::ChangeProcessorMock() : ChangeProcessor(NULL) {}
+
+ChangeProcessorMock::~ChangeProcessorMock() {}
+
+}  // namespace browser_sync
diff --git a/chrome/browser/sync/glue/change_processor_mock.h b/chrome/browser/sync/glue/change_processor_mock.h
index e138937..d74e40e 100644
--- a/chrome/browser/sync/glue/change_processor_mock.h
+++ b/chrome/browser/sync/glue/change_processor_mock.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
@@ -17,7 +17,8 @@ namespace browser_sync {
 
 class ChangeProcessorMock : public ChangeProcessor {
  public:
-  ChangeProcessorMock() : ChangeProcessor(NULL) {}
+  ChangeProcessorMock();
+  virtual ~ChangeProcessorMock();
   MOCK_METHOD3(ApplyChangesFromSyncModel,
                void(const sync_api::BaseTransaction* trans,
                     const sync_api::SyncManager::ChangeRecord* changes,
diff --git a/chrome/browser/sync/glue/data_type_controller_mock.cc b/chrome/browser/sync/glue/data_type_controller_mock.cc
new file mode 100644
index 0000000..7909b86
--- /dev/null
+++ b/chrome/browser/sync/glue/data_type_controller_mock.cc
@@ -0,0 +1,13 @@
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chrome/browser/sync/glue/data_type_controller_mock.h"
+
+namespace browser_sync {
+
+DataTypeControllerMock::DataTypeControllerMock() {}
+
+DataTypeControllerMock::~DataTypeControllerMock() {}
+
+}  // namespace browser_sync
diff --git a/chrome/browser/sync/glue/data_type_controller_mock.h b/chrome/browser/sync/glue/data_type_controller_mock.h
index 09ec652..83d0b6b 100644
--- a/chrome/browser/sync/glue/data_type_controller_mock.h
+++ b/chrome/browser/sync/glue/data_type_controller_mock.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
@@ -13,6 +13,9 @@ namespace browser_sync {
 
 class DataTypeControllerMock : public DataTypeController {
  public:
+  DataTypeControllerMock();
+  virtual ~DataTypeControllerMock();
+
   MOCK_METHOD1(Start, void(StartCallback* start_callback));
   MOCK_METHOD0(Stop, void());
   MOCK_METHOD0(enabled, bool());
diff --git a/chrome/browser/sync/glue/data_type_manager_mock.cc b/chrome/browser/sync/glue/data_type_manager_mock.cc
new file mode 100644
index 0000000..9cc445e
--- /dev/null
+++ b/chrome/browser/sync/glue/data_type_manager_mock.cc
@@ -0,0 +1,24 @@
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chrome/browser/sync/glue/data_type_manager_mock.h"
+
+namespace browser_sync {
+
+DataTypeManagerMock::DataTypeManagerMock()
+    : result_(OK) {
+  // By default, calling Configure will send a SYNC_CONFIGURE_START
+  // and SYNC_CONFIGURE_DONE notification with a DataTypeManager::OK
+  // detail.
+  ON_CALL(*this, Configure(testing::_)).
+      WillByDefault(testing::DoAll(
+          NotifyFromDataTypeManager(this,
+                                    NotificationType::SYNC_CONFIGURE_START),
+          NotifyFromDataTypeManagerWithResult
+          (this, NotificationType::SYNC_CONFIGURE_DONE, &result_)));
+}
+
+DataTypeManagerMock::~DataTypeManagerMock() {}
+
+}  // namespace browser_sync
diff --git a/chrome/browser/sync/glue/data_type_manager_mock.h b/chrome/browser/sync/glue/data_type_manager_mock.h
index 2a1705a..05a3665 100644
--- a/chrome/browser/sync/glue/data_type_manager_mock.h
+++ b/chrome/browser/sync/glue/data_type_manager_mock.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
@@ -30,17 +30,8 @@ namespace browser_sync {
 
 class DataTypeManagerMock : public DataTypeManager {
  public:
-  DataTypeManagerMock() : result_(OK) {
-    // By default, calling Configure will send a SYNC_CONFIGURE_START
-    // and SYNC_CONFIGURE_DONE notification with a DataTypeManager::OK
-    // detail.
-    ON_CALL(*this, Configure(testing::_)).
-        WillByDefault(testing::DoAll(
-            NotifyFromDataTypeManager(this,
-                NotificationType::SYNC_CONFIGURE_START),
-            NotifyFromDataTypeManagerWithResult
-                 (this, NotificationType::SYNC_CONFIGURE_DONE, &result_)));
-  }
+  DataTypeManagerMock();
+  virtual ~DataTypeManagerMock();
 
   MOCK_METHOD1(Configure, void(const TypeSet&));
   MOCK_METHOD0(Stop, void());
diff --git a/chrome/browser/sync/glue/database_model_worker.cc b/chrome/browser/sync/glue/database_model_worker.cc
index b09c6c6..91bba5b 100644
--- a/chrome/browser/sync/glue/database_model_worker.cc
+++ b/chrome/browser/sync/glue/database_model_worker.cc
@@ -4,7 +4,7 @@
 
 #include "chrome/browser/sync/glue/database_model_worker.h"
 
-#include "base/waitable_event.h"
+#include "base/synchronization/waitable_event.h"
 #include "chrome/browser/browser_thread.h"
 
 using base::WaitableEvent;
diff --git a/chrome/browser/sync/glue/database_model_worker_unittest.cc b/chrome/browser/sync/glue/database_model_worker_unittest.cc
index 8d399b1..7f60cea 100644
--- a/chrome/browser/sync/glue/database_model_worker_unittest.cc
+++ b/chrome/browser/sync/glue/database_model_worker_unittest.cc
@@ -5,7 +5,7 @@
 #include "base/callback.h"
 #include "base/message_loop.h"
 #include "base/scoped_ptr.h"
-#include "base/thread.h"
+#include "base/threading/thread.h"
 #include "base/timer.h"
 #include "chrome/browser/browser_thread.h"
 #include "chrome/browser/sync/glue/database_model_worker.h"
diff --git a/chrome/browser/sync/glue/foreign_session_tracker.cc b/chrome/browser/sync/glue/foreign_session_tracker.cc
new file mode 100644
index 0000000..6db5c9c
--- /dev/null
+++ b/chrome/browser/sync/glue/foreign_session_tracker.cc
@@ -0,0 +1,143 @@
+// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chrome/browser/sync/glue/foreign_session_tracker.h"
+#include "chrome/browser/sync/glue/session_model_associator.h"
+
+namespace browser_sync {
+
+
+ForeignSessionTracker::ForeignSessionTracker() {
+}
+
+ForeignSessionTracker::~ForeignSessionTracker() {
+  clear();
+}
+
+bool ForeignSessionTracker::LookupAllForeignSessions(
+    std::vector<const ForeignSession*>* sessions) {
+  DCHECK(sessions);
+  // Fill vector of sessions from our foreign session map.
+  for (ForeignSessionMap::const_iterator i =
+    foreign_session_map_.begin(); i != foreign_session_map_.end(); ++i) {
+    // Only include sessions with open tabs.
+    ForeignSession* foreign_session = i->second;
+    if (foreign_session->windows.size() > 0 &&
+        !SessionModelAssociator::SessionWindowHasNoTabsToSync(
+            *foreign_session->windows[0])) {
+      sessions->push_back(foreign_session);
+    }
+  }
+
+  if (sessions->size() > 0)
+    return true;
+  else
+    return false;
+}
+
+bool ForeignSessionTracker::LookupSessionWindows(
+    const std::string& foreign_session_tag,
+    std::vector<SessionWindow*>* windows) {
+  DCHECK(windows);
+  ForeignSessionMap::iterator iter = foreign_session_map_.find(
+      foreign_session_tag);
+  if (iter == foreign_session_map_.end())
+    return false;
+  *windows = iter->second->windows;
+  return true;
+}
+
+bool ForeignSessionTracker::LookupSessionTab(
+    const std::string& tag,
+    SessionID::id_type tab_id,
+    const SessionTab** tab) {
+  DCHECK(tab);
+  if (foreign_tab_map_.find(tag) == foreign_tab_map_.end()) {
+    // We have no record of this session.
+    *tab = NULL;
+    return false;
+  }
+  if (foreign_tab_map_[tag]->find(tab_id) == foreign_tab_map_[tag]->end()) {
+    // We have no record of this tab.
+    *tab = NULL;
+    return false;
+  }
+  *tab = (*foreign_tab_map_[tag])[tab_id];
+  return true;
+}
+
+ForeignSession* ForeignSessionTracker::GetForeignSession(
+    const std::string& foreign_session_tag) {
+  scoped_ptr<ForeignSession> foreign_session;
+  if (foreign_session_map_.find(foreign_session_tag) !=
+      foreign_session_map_.end()) {
+    foreign_session.reset(foreign_session_map_[foreign_session_tag]);
+  } else {
+    foreign_session.reset(new ForeignSession);
+    foreign_session->foreign_session_tag = foreign_session_tag;
+    foreign_session_map_[foreign_session_tag] = foreign_session.get();
+  }
+  DCHECK(foreign_session.get());
+  return foreign_session.release();
+}
+
+bool ForeignSessionTracker::DeleteForeignSession(
+    const std::string& foreign_session_tag) {
+    ForeignSessionMap::iterator iter =
+        foreign_session_map_.find(foreign_session_tag);
+  if (iter != foreign_session_map_.end()) {
+    delete iter->second;  // Delete the ForeignSession object.
+    foreign_session_map_.erase(iter);
+    return true;
+  } else {
+    return false;
+  }
+}
+
+SessionTab* ForeignSessionTracker::GetSessionTab(
+    const std::string& foreign_session_tag,
+    SessionID::id_type tab_id,
+    bool has_window) {
+  if (foreign_tab_map_.find(foreign_session_tag) == foreign_tab_map_.end())
+    foreign_tab_map_[foreign_session_tag] = new IDToSessionTabMap;
+  scoped_ptr<SessionTab> tab;
+  IDToSessionTabMap::iterator iter =
+      foreign_tab_map_[foreign_session_tag]->find(tab_id);
+  if (iter != foreign_tab_map_[foreign_session_tag]->end()) {
+    tab.reset(iter->second);
+    if (has_window)  // This tab is linked to a window, so it's not an orphan.
+      unmapped_tabs_.erase(tab.get());
+    VLOG(1) << "Associating " << foreign_session_tag << "'s seen tab " <<
+        tab_id  << " at " << tab.get();
+  } else {
+    tab.reset(new SessionTab());
+    (*foreign_tab_map_[foreign_session_tag])[tab_id] = tab.get();
+    if (!has_window)  // This tab is not linked to a window, it's an orphan.
+    unmapped_tabs_.insert(tab.get());
+    VLOG(1) << "Associating " << foreign_session_tag << "'s new tab " <<
+        tab_id  << " at " << tab.get();
+  }
+  DCHECK(tab.get());
+  return tab.release();
+}
+
+void ForeignSessionTracker::clear() {
+  // Delete ForeignSession objects (which also deletes all their windows/tabs).
+  STLDeleteContainerPairSecondPointers(foreign_session_map_.begin(),
+      foreign_session_map_.end());
+  foreign_session_map_.clear();
+
+  // Delete IDToSessTab maps. Does not delete the SessionTab objects, because
+  // they should already be referenced through foreign_session_map_.
+  STLDeleteContainerPairSecondPointers(foreign_tab_map_.begin(),
+      foreign_tab_map_.end());
+  foreign_tab_map_.clear();
+
+  // Go through and delete any tabs we had allocated but had not yet placed into
+  // a ForeignSessionobject.
+  STLDeleteContainerPointers(unmapped_tabs_.begin(), unmapped_tabs_.end());
+  unmapped_tabs_.clear();
+}
+
+}  // namespace browser_sync
diff --git a/chrome/browser/sync/glue/foreign_session_tracker.h b/chrome/browser/sync/glue/foreign_session_tracker.h
new file mode 100644
index 0000000..dd99455
--- /dev/null
+++ b/chrome/browser/sync/glue/foreign_session_tracker.h
@@ -0,0 +1,111 @@
+// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CHROME_BROWSER_SYNC_GLUE_FOREIGN_SESSION_TRACKER_H_
+#define CHROME_BROWSER_SYNC_GLUE_FOREIGN_SESSION_TRACKER_H_
+#pragma once
+
+#include <map>
+#include <set>
+#include <string>
+#include <vector>
+
+#include "base/basictypes.h"
+#include "base/scoped_vector.h"
+#include "chrome/browser/sessions/session_id.h"
+#include "chrome/browser/sessions/session_types.h"
+
+namespace browser_sync {
+
+// Class to manage foreign sessions. The tracker will own all ForeignSession
+// and SessionTab objects it creates, and deletes them appropriately on
+// destruction.
+class ForeignSessionTracker {
+ public:
+  ForeignSessionTracker();
+  ~ForeignSessionTracker();
+
+  // Fill a preallocated vector with all foreign sessions we're tracking.
+  // Returns true if we had foreign sessions to fill it with, false otherwise.
+  bool LookupAllForeignSessions(std::vector<const ForeignSession*>* sessions);
+
+  // Attempts to look up the session windows associatd with the foreign session
+  // given by |foreign_session_tag|.
+  // If lookup succeeds:
+  // - Fills windows with the SessionWindow pointers, returns true.
+  // Else
+  // - Returns false.
+  bool LookupSessionWindows(const std::string& foreign_session_tag,
+                            std::vector<SessionWindow*>* windows);
+
+  // Attempts to look up the foreign tab associated with the given tag and tab
+  // id.
+  // If lookup succeeds:
+  // - Sets tab to point to the SessionTab, and returns true.
+  // Else
+  // - Returns false, tab is set to NULL.
+  bool LookupSessionTab(const std::string& foreign_session_tag,
+                        SessionID::id_type tab_id,
+                        const SessionTab** tab);
+
+  // Returns a pointer to the ForeignSession object associated with
+  // foreign_session_tag. If none exists, creates one and returns its pointer.
+  ForeignSession* GetForeignSession(const std::string& foreign_session_tag);
+
+  // Deletes the foreign session associated with |foreign_session_tag| if it
+  // exists.
+  // Returns true if the session existed and was deleted, false otherwise.
+  bool DeleteForeignSession(const std::string& foreign_session_tag);
+
+  // Returns a pointer to the SessionTab object associated with |tab_id| for
+  // the session specified with |foreign_session_tag|. If none exists, creates
+  // one and returns its pointer.
+  // |has_window| determines if newly created tabs are added to the pool of
+  // orphaned tabs (thos which can't be reached by traversing foreign sessions).
+  SessionTab* GetSessionTab(const std::string& foreign_session_tag,
+                            SessionID::id_type tab_id,
+                            bool has_window);
+
+  // Free the memory for all dynamically allocated objects and clear the
+  // tracking structures.
+  void clear();
+
+  inline bool empty() {
+    return foreign_tab_map_.empty() && foreign_session_map_.empty();
+  }
+
+  inline size_t num_foreign_sessions() {
+    return foreign_session_map_.size();
+  }
+
+  inline size_t num_foreign_tabs(const std::string& foreign_session_tag) {
+    if (foreign_tab_map_.find(foreign_session_tag) != foreign_tab_map_.end()) {
+      return foreign_tab_map_[foreign_session_tag]->size();
+    } else {
+      return 0;
+    }
+  }
+ private:
+  // Datatypes for accessing foreign tab data.
+  typedef std::map<SessionID::id_type, SessionTab*> IDToSessionTabMap;
+  typedef std::map<std::string, IDToSessionTabMap*> ForeignTabMap;
+  typedef std::map<std::string, ForeignSession*> ForeignSessionMap;
+
+  // Per foreign client mapping of their tab id's to their SessionTab objects.
+  ForeignTabMap foreign_tab_map_;
+
+  // Map of foreign sessions, accessed by the foreign client id.
+  ForeignSessionMap foreign_session_map_;
+
+  // The set of foreign tabs that we have seen, and created SessionTab objects
+  // for, but have not yet mapped to ForeignSessions. These are temporarily
+  // orphaned tabs, and won't be deleted if we delete foreign_session_map_.
+  std::set<SessionTab*> unmapped_tabs_;
+
+  DISALLOW_COPY_AND_ASSIGN(ForeignSessionTracker);
+};
+
+}  // namespace browser_sync
+
+#endif  // CHROME_BROWSER_SYNC_GLUE_FOREIGN_SESSION_TRACKER_H_
diff --git a/chrome/browser/sync/glue/history_model_worker.cc b/chrome/browser/sync/glue/history_model_worker.cc
index 9b0ea50..e880476 100644
--- a/chrome/browser/sync/glue/history_model_worker.cc
+++ b/chrome/browser/sync/glue/history_model_worker.cc
@@ -7,7 +7,7 @@
 #include "base/message_loop.h"
 #include "base/ref_counted.h"
 #include "base/task.h"
-#include "base/waitable_event.h"
+#include "base/synchronization/waitable_event.h"
 #include "chrome/browser/history/history.h"
 
 using base::WaitableEvent;
diff --git a/chrome/browser/sync/glue/http_bridge.cc b/chrome/browser/sync/glue/http_bridge.cc
index 8dc2b6f..2ec5a1b 100644
--- a/chrome/browser/sync/glue/http_bridge.cc
+++ b/chrome/browser/sync/glue/http_bridge.cc
@@ -193,6 +193,7 @@ void HttpBridge::MakeAsynchronousPost() {
   url_poster_->set_request_context(context_getter_for_request_);
   url_poster_->set_upload_data(content_type_, request_content_);
   url_poster_->set_extra_request_headers(extra_headers_);
+  url_poster_->set_load_flags(net::LOAD_DO_NOT_SEND_COOKIES);
   url_poster_->Start();
 }
 
diff --git a/chrome/browser/sync/glue/http_bridge.h b/chrome/browser/sync/glue/http_bridge.h
index 530c215..5fb2419 100644
--- a/chrome/browser/sync/glue/http_bridge.h
+++ b/chrome/browser/sync/glue/http_bridge.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
@@ -9,7 +9,7 @@
 #include <string>
 
 #include "base/ref_counted.h"
-#include "base/waitable_event.h"
+#include "base/synchronization/waitable_event.h"
 #include "chrome/browser/sync/engine/syncapi.h"
 #include "chrome/common/net/url_fetcher.h"
 #include "chrome/common/net/url_request_context_getter.h"
@@ -41,13 +41,13 @@ class HttpBridge : public base::RefCountedThreadSafe<HttpBridge>,
   // 2) avoids ifdefs for now
   // 3) not sure we want to strictly follow settings for cookie policy,
   //    accept lang/charset, since changing these could break syncing.
-  class RequestContext : public URLRequestContext {
+  class RequestContext : public net::URLRequestContext {
    public:
     // |baseline_context| is used to obtain the accept-language,
     // accept-charsets, and proxy service information for bridged requests.
     // Typically |baseline_context| should be the URLRequestContext of the
     // currently active profile.
-    explicit RequestContext(URLRequestContext* baseline_context);
+    explicit RequestContext(net::URLRequestContext* baseline_context);
 
     // Set the user agent for requests using this context. The default is
     // the browser's UA string.
@@ -57,11 +57,7 @@ class HttpBridge : public base::RefCountedThreadSafe<HttpBridge>,
       // If the user agent is set explicitly return that, otherwise call the
       // base class method to return default value.
       return user_agent_.empty() ?
-          URLRequestContext::GetUserAgent(url) : user_agent_;
-    }
-
-    virtual bool AllowSendingCookies(const net::URLRequest* request) const {
-      return false;
+          net::URLRequestContext::GetUserAgent(url) : user_agent_;
     }
 
    private:
@@ -69,7 +65,7 @@ class HttpBridge : public base::RefCountedThreadSafe<HttpBridge>,
     ~RequestContext();
 
     std::string user_agent_;
-    URLRequestContext* baseline_context_;
+    net::URLRequestContext* baseline_context_;
 
     DISALLOW_COPY_AND_ASSIGN(RequestContext);
   };
@@ -84,7 +80,7 @@ class HttpBridge : public base::RefCountedThreadSafe<HttpBridge>,
     bool is_user_agent_set() const { return !user_agent_.empty(); }
 
     // URLRequestContextGetter implementation.
-    virtual URLRequestContext* GetURLRequestContext();
+    virtual net::URLRequestContext* GetURLRequestContext();
     virtual scoped_refptr<base::MessageLoopProxy> GetIOMessageLoopProxy() const;
 
    private:
@@ -121,8 +117,9 @@ class HttpBridge : public base::RefCountedThreadSafe<HttpBridge>,
       const std::string& name) const;
 
   // URLFetcher::Delegate implementation.
-  virtual void OnURLFetchComplete(const URLFetcher* source, const GURL& url,
-                                  const URLRequestStatus& status,
+  virtual void OnURLFetchComplete(const URLFetcher* source,
+                                  const GURL& url,
+                                  const net::URLRequestStatus& status,
                                   int response_code,
                                   const ResponseCookies& cookies,
                                   const std::string& data);
diff --git a/chrome/browser/sync/glue/http_bridge_unittest.cc b/chrome/browser/sync/glue/http_bridge_unittest.cc
index 57fca13..f9aa32c 100644
--- a/chrome/browser/sync/glue/http_bridge_unittest.cc
+++ b/chrome/browser/sync/glue/http_bridge_unittest.cc
@@ -3,7 +3,7 @@
 // found in the LICENSE file.
 
 #include "base/message_loop_proxy.h"
-#include "base/thread.h"
+#include "base/threading/thread.h"
 #include "chrome/browser/browser_thread.h"
 #include "chrome/browser/sync/glue/http_bridge.h"
 #include "chrome/common/net/test_url_fetcher_factory.h"
diff --git a/chrome/browser/sync/glue/password_model_worker.cc b/chrome/browser/sync/glue/password_model_worker.cc
index c06f33f..6132a03 100644
--- a/chrome/browser/sync/glue/password_model_worker.cc
+++ b/chrome/browser/sync/glue/password_model_worker.cc
@@ -7,7 +7,7 @@
 #include "base/callback.h"
 #include "base/ref_counted.h"
 #include "base/task.h"
-#include "base/waitable_event.h"
+#include "base/synchronization/waitable_event.h"
 #include "chrome/browser/password_manager/password_store.h"
 
 using base::WaitableEvent;
diff --git a/chrome/browser/sync/glue/session_change_processor.cc b/chrome/browser/sync/glue/session_change_processor.cc
index ca0b166..8823af0 100644
--- a/chrome/browser/sync/glue/session_change_processor.cc
+++ b/chrome/browser/sync/glue/session_change_processor.cc
@@ -10,9 +10,10 @@
 
 #include "base/logging.h"
 #include "base/scoped_vector.h"
-#include "chrome/browser/browser_thread.h"
 #include "chrome/browser/sync/engine/syncapi.h"
 #include "chrome/browser/sync/glue/session_model_associator.h"
+#include "chrome/browser/tab_contents/navigation_controller.h"
+#include "chrome/browser/tab_contents/tab_contents.h"
 #include "chrome/common/notification_details.h"
 #include "chrome/common/notification_service.h"
 #include "chrome/common/notification_source.h"
@@ -40,18 +41,95 @@ void SessionChangeProcessor::Observe(NotificationType type,
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   DCHECK(running());
   DCHECK(profile_);
+
+  // Track which windows and/or tabs are modified.
+  std::vector<TabContents*> modified_tabs;
+  bool windows_changed = false;
   switch (type.value) {
-    case NotificationType::SESSION_SERVICE_SAVED: {
-      std::string tag = session_model_associator_->GetCurrentMachineTag();
-      DCHECK_EQ(Source<Profile>(source).ptr(), profile_);
-      session_model_associator_->UpdateSyncModelDataFromClient();
+    case NotificationType::BROWSER_OPENED: {
+      Browser* browser = Source<Browser>(source).ptr();
+      if (browser->profile() != profile_) {
+        return;
+      }
+
+      windows_changed = true;
+      break;
+    }
+
+    case NotificationType::TAB_PARENTED: {
+      NavigationController* controller =
+          Source<NavigationController>(source).ptr();
+      if (controller->profile() != profile_) {
+        return;
+      }
+      windows_changed = true;
+      modified_tabs.push_back(controller->tab_contents());
+      break;
+    }
+
+    case NotificationType::TAB_CLOSED: {
+      NavigationController* controller =
+          Source<NavigationController>(source).ptr();
+      if (controller->profile() != profile_) {
+        return;
+      }
+      windows_changed = true;
+      modified_tabs.push_back(controller->tab_contents());
+      break;
+    }
+
+    case NotificationType::NAV_LIST_PRUNED: {
+      NavigationController* controller =
+          Source<NavigationController>(source).ptr();
+      if (controller->profile() != profile_) {
+        return;
+      }
+      modified_tabs.push_back(controller->tab_contents());
+      break;
+    }
+
+    case NotificationType::NAV_ENTRY_CHANGED: {
+      NavigationController* controller =
+          Source<NavigationController>(source).ptr();
+      if (controller->profile() != profile_) {
+        return;
+      }
+      modified_tabs.push_back(controller->tab_contents());
+      break;
+    }
+
+    case NotificationType::NAV_ENTRY_COMMITTED: {
+      NavigationController* controller =
+          Source<NavigationController>(source).ptr();
+      if (controller->profile() != profile_) {
+        return;
+      }
+      modified_tabs.push_back(controller->tab_contents());
+      break;
+    }
+
+    case NotificationType::TAB_CONTENTS_APPLICATION_EXTENSION_CHANGED: {
+      TabContents* tab_contents = Source<TabContents>(source).ptr();
+      DCHECK(tab_contents);
+      if (tab_contents->profile() != profile_) {
+        return;
+      }
+      if (tab_contents->extension_app()) {
+        modified_tabs.push_back(tab_contents);
+      }
       break;
     }
     default:
-      LOG(DFATAL) << "Received unexpected notification of type "
+      LOG(ERROR) << "Received unexpected notification of type "
                   << type.value;
       break;
   }
+
+  // Associate windows first to ensure tabs have homes.
+  if (windows_changed)
+    session_model_associator_->ReassociateWindows(false);
+  if (!modified_tabs.empty())
+    session_model_associator_->ReassociateTabs(modified_tabs);
 }
 
 void SessionChangeProcessor::ApplyChangesFromSyncModel(
@@ -65,10 +143,50 @@ void SessionChangeProcessor::ApplyChangesFromSyncModel(
 
   StopObserving();
 
-  // This currently ignores the tracked changes and rebuilds the sessions from
-  // all the session sync nodes.
-  // TODO(zea): Make use of |changes| to adjust only modified sessions.
-  session_model_associator_->UpdateFromSyncModel(trans);
+  sync_api::ReadNode root(trans);
+  if (!root.InitByTagLookup(kSessionsTag)) {
+    error_handler()->OnUnrecoverableError(FROM_HERE,
+        "Sessions root node lookup failed.");
+    return;
+  }
+
+  for (int i = 0; i < change_count; ++i) {
+    const sync_api::SyncManager::ChangeRecord& change = changes[i];
+    sync_api::SyncManager::ChangeRecord::Action action(change.action);
+    if (sync_api::SyncManager::ChangeRecord::ACTION_DELETE == action) {
+      // Deletions should only be for a foreign client itself, and hence affect
+      // the header node, never a tab node.
+      sync_api::ReadNode node(trans);
+      if (!node.InitByIdLookup(change.id)) {
+        error_handler()->OnUnrecoverableError(FROM_HERE,
+                                              "Session node lookup failed.");
+        return;
+      }
+      DCHECK_EQ(node.GetModelType(), syncable::SESSIONS);
+      const sync_pb::SessionSpecifics& specifics = node.GetSessionSpecifics();
+      session_model_associator_->DisassociateForeignSession(
+          specifics.session_tag());
+      continue;
+    }
+
+    // Handle an update or add.
+    sync_api::ReadNode sync_node(trans);
+    if (!sync_node.InitByIdLookup(change.id)) {
+      error_handler()->OnUnrecoverableError(FROM_HERE,
+          "Session node lookup failed.");
+      return;
+    }
+
+    // Check that the changed node is a child of the session folder.
+    DCHECK(root.GetId() == sync_node.GetParentId());
+    DCHECK(syncable::SESSIONS == sync_node.GetModelType());
+
+    const sync_pb::SessionSpecifics& specifics(
+        sync_node.GetSessionSpecifics());
+    const int64 mtime = sync_node.GetModificationTime();
+    // Model associator handles foreign session update and add the same.
+    session_model_associator_->AssociateForeignSpecifics(specifics, mtime);
+  }
 
   // Notify foreign session handlers that there are new sessions.
   NotificationService::current()->Notify(
@@ -96,9 +214,21 @@ void SessionChangeProcessor::StopImpl() {
 void SessionChangeProcessor::StartObserving() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   DCHECK(profile_);
-  notification_registrar_.Add(
-      this, NotificationType::SESSION_SERVICE_SAVED,
-      Source<Profile>(profile_));
+  notification_registrar_.Add(this, NotificationType::TAB_PARENTED,
+      NotificationService::AllSources());
+  notification_registrar_.Add(this, NotificationType::TAB_CLOSED,
+      NotificationService::AllSources());
+  notification_registrar_.Add(this, NotificationType::NAV_LIST_PRUNED,
+      NotificationService::AllSources());
+  notification_registrar_.Add(this, NotificationType::NAV_ENTRY_CHANGED,
+      NotificationService::AllSources());
+  notification_registrar_.Add(this, NotificationType::NAV_ENTRY_COMMITTED,
+      NotificationService::AllSources());
+  notification_registrar_.Add(this, NotificationType::BROWSER_OPENED,
+      NotificationService::AllSources());
+  notification_registrar_.Add(this,
+      NotificationType::TAB_CONTENTS_APPLICATION_EXTENSION_CHANGED,
+      NotificationService::AllSources());
 }
 
 void SessionChangeProcessor::StopObserving() {
diff --git a/chrome/browser/sync/glue/session_model_associator.cc b/chrome/browser/sync/glue/session_model_associator.cc
index 5ec89be..8c8cb6d 100644
--- a/chrome/browser/sync/glue/session_model_associator.cc
+++ b/chrome/browser/sync/glue/session_model_associator.cc
@@ -4,15 +4,19 @@
 
 #include "chrome/browser/sync/glue/session_model_associator.h"
 
+#include <algorithm>
 #include <utility>
 
 #include "base/logging.h"
-#include "base/string_util.h"
-#include "base/utf_string_conversions.h"
+#include "chrome/browser/browser_list.h"
+#include "chrome/browser/browser_window.h"
 #include "chrome/browser/profiles/profile.h"
-#include "chrome/browser/sessions/session_id.h"
 #include "chrome/browser/sync/profile_sync_service.h"
 #include "chrome/browser/sync/syncable/syncable.h"
+#include "chrome/browser/tab_contents/navigation_controller.h"
+#include "chrome/browser/tab_contents/navigation_entry.h"
+#include "chrome/browser/tabs/tab_strip_model.h"
+#include "chrome/common/extensions/extension.h"
 #include "chrome/common/notification_details.h"
 #include "chrome/common/notification_service.h"
 #include "chrome/common/url_constants.h"
@@ -20,15 +24,18 @@
 namespace browser_sync {
 
 namespace {
-
 static const char kNoSessionsFolderError[] =
     "Server did not create the top-level sessions node. We "
     "might be running against an out-of-date server.";
 
+// The maximum number of navigations in each direction we care to sync.
+static const int max_sync_navigation_count = 6;
 }  // namespace
 
-SessionModelAssociator::SessionModelAssociator(
-    ProfileSyncService* sync_service) : sync_service_(sync_service) {
+SessionModelAssociator::SessionModelAssociator(ProfileSyncService* sync_service)
+    : tab_pool_(sync_service),
+      local_session_syncid_(sync_api::kInvalidId),
+      sync_service_(sync_service) {
   DCHECK(CalledOnValidThread());
   DCHECK(sync_service_);
 }
@@ -37,80 +44,10 @@ SessionModelAssociator::~SessionModelAssociator() {
   DCHECK(CalledOnValidThread());
 }
 
-bool SessionModelAssociator::AssociateModels() {
-  DCHECK(CalledOnValidThread());
-
-  // Make sure we have a machine tag.
-  if (current_machine_tag_.empty())
-    InitializeCurrentMachineTag();  // Creates a syncable::BaseTransaction.
-
-  {
-    // Do an initial update from sync model (in case we just re-enabled and
-    // already had data).
-    sync_api::ReadTransaction trans(
-        sync_service_->backend()->GetUserShareHandle());
-    UpdateFromSyncModel(&trans);
-  }
-
-  // Check if anything has changed on the client side.
-  UpdateSyncModelDataFromClient();
-  return true;
-}
-
-bool SessionModelAssociator::ChromeModelHasUserCreatedNodes(
-    bool* has_nodes) {
-  DCHECK(CalledOnValidThread());
-  CHECK(has_nodes);
-  // This is wrong, but this function is unused, anyway.
-  *has_nodes = true;
-  return true;
-}
-
-bool SessionModelAssociator::DisassociateModels() {
-  specifics_.clear();
-
-  // There is no local model stored with which to disassociate, just notify
-  // foreign session handlers.
-  NotificationService::current()->Notify(
-      NotificationType::FOREIGN_SESSION_DISABLED,
-      NotificationService::AllSources(),
-      NotificationService::NoDetails());
-  return true;
-}
-
-const sync_pb::SessionSpecifics* SessionModelAssociator::
-    GetChromeNodeFromSyncId(int64 sync_id) {
-  sync_api::ReadTransaction trans(
-    sync_service_->backend()->GetUserShareHandle());
-  sync_api::ReadNode node(&trans);
-  if (!node.InitByIdLookup(sync_id))
-    return NULL;
-  return new sync_pb::SessionSpecifics(node.GetSessionSpecifics());
-}
-
-bool SessionModelAssociator::GetSyncIdForTaggedNode(const std::string* tag,
-    int64* sync_id) {
-  sync_api::ReadTransaction trans(
-      sync_service_->backend()->GetUserShareHandle());
-  sync_api::ReadNode node(&trans);
-  if (!node.InitByClientTagLookup(syncable::SESSIONS, *tag))
-    return false;
-  *sync_id = node.GetId();
-  return true;
-}
-
-int64 SessionModelAssociator::GetSyncIdFromChromeId(const std::string& id) {
-  sync_api::ReadTransaction trans(
-      sync_service_->backend()->GetUserShareHandle());
-  sync_api::ReadNode node(&trans);
-  if (!node.InitByClientTagLookup(syncable::SESSIONS, id))
-    return sync_api::kInvalidId;
-  return node.GetId();
-}
-
 bool SessionModelAssociator::InitSyncNodeFromChromeId(
     const std::string& id,
     sync_api::BaseNode* sync_node) {
+  NOTREACHED();
   return false;
 }
 
@@ -131,138 +68,212 @@ bool SessionModelAssociator::SyncModelHasUserCreatedNodes(bool* has_nodes) {
   return true;
 }
 
-std::string SessionModelAssociator::GetCurrentMachineTag() {
-  DCHECK(!current_machine_tag_.empty());
-  return current_machine_tag_;
+int64 SessionModelAssociator::GetSyncIdFromChromeId(const size_t& id) {
+  DCHECK(CalledOnValidThread());
+  return GetSyncIdFromSessionTag(TabIdToTag(GetCurrentMachineTag(), id));
 }
 
-void SessionModelAssociator::UpdateSyncModelDataFromClient() {
+int64 SessionModelAssociator::GetSyncIdFromSessionTag(const std::string& tag) {
   DCHECK(CalledOnValidThread());
-  SessionService::SessionCallback* callback =
-      NewCallback(this, &SessionModelAssociator::OnGotSession);
-  // TODO(jerrica): Stop current race condition, possibly make new method in
-  // session service, which only grabs the windows from memory.
-  GetSessionService()->GetCurrentSession(&consumer_, callback);
+  sync_api::ReadTransaction trans(
+      sync_service_->backend()->GetUserShareHandle());
+  sync_api::ReadNode node(&trans);
+  if (!node.InitByClientTagLookup(syncable::SESSIONS, tag))
+    return sync_api::kInvalidId;
+  return node.GetId();
 }
-
-// TODO(zea): Don't recreate sessions_ vector from scratch each time. This
-// will involve knowing which sessions have been changed (a different data
-// structure will probably be better too).
-bool SessionModelAssociator::UpdateFromSyncModel(
-    const sync_api::BaseTransaction* trans) {
+void SessionModelAssociator::ReassociateWindows(bool reload_tabs) {
   DCHECK(CalledOnValidThread());
+  sync_pb::SessionSpecifics specifics;
+  specifics.set_session_tag(GetCurrentMachineTag());
+  sync_pb::SessionHeader* header_s = specifics.mutable_header();
+
+  for (BrowserList::const_iterator i = BrowserList::begin();
+       i != BrowserList::end(); ++i) {
+    // Make sure the browser has tabs and a window. Browsers destructor
+    // removes itself from the BrowserList. When a browser is closed the
+    // destructor is not necessarily run immediately. This means its possible
+    // for us to get a handle to a browser that is about to be removed. If
+    // the tab count is 0 or the window is NULL, the browser is about to be
+    // deleted, so we ignore it.
+    if (ShouldSyncWindowType((*i)->type()) && (*i)->tab_count() &&
+        (*i)->window()) {
+      sync_pb::SessionWindow window_s;
+      SessionID::id_type window_id = (*i)->session_id().id();
+      VLOG(1) << "Reassociating window " << window_id << " with " <<
+          (*i)->tab_count() << " tabs.";
+      window_s.set_window_id(window_id);
+      window_s.set_selected_tab_index((*i)->selected_index());
+      if ((*i)->type() ==
+          Browser::TYPE_NORMAL) {
+        window_s.set_browser_type(
+            sync_pb::SessionWindow_BrowserType_TYPE_NORMAL);
+      } else {
+        window_s.set_browser_type(
+            sync_pb::SessionWindow_BrowserType_TYPE_POPUP);
+      }
 
-  // Rebuild specifics_ vector
-  specifics_.clear();
-  if (!QuerySyncModel(trans, specifics_)) {
-    LOG(ERROR) << "SessionModelAssociator failed to updated from sync model";
-    return false;
+      // Store the order of tabs.
+      bool found_tabs = false;
+      for (int j = 0; j < (*i)->tab_count(); ++j) {
+        TabContents* tab = (*i)->GetTabContentsAt(j);
+        DCHECK(tab);
+        if (IsValidTab(*tab)) {
+          found_tabs = true;
+          window_s.add_tab(tab->controller().session_id().id());
+          if (reload_tabs) {
+            ReassociateTab(*tab);
+          }
+        }
+      }
+      // Only add a window if it contains valid tabs.
+      if (found_tabs) {
+        sync_pb::SessionWindow* header_window = header_s->add_window();
+        *header_window = window_s;
+      }
+    }
   }
 
-  return true;
+  sync_api::WriteTransaction trans(
+      sync_service_->backend()->GetUserShareHandle());
+  sync_api::WriteNode header_node(&trans);
+  if (!header_node.InitByIdLookup(local_session_syncid_)) {
+    LOG(ERROR) << "Failed to load local session header node.";
+    return;
+  }
+  header_node.SetSessionSpecifics(specifics);
 }
 
-bool SessionModelAssociator::QuerySyncModel(
-    const sync_api::BaseTransaction* trans,
-    std::vector<const sync_pb::SessionSpecifics*>& specifics) {
-  DCHECK(CalledOnValidThread());
-  sync_api::ReadNode root(trans);
-  if (!root.InitByTagLookup(kSessionsTag)) {
-    LOG(ERROR) << kNoSessionsFolderError;
-    return false;
+// Static.
+bool SessionModelAssociator::ShouldSyncWindowType(const Browser::Type& type) {
+  switch (type) {
+    case Browser::TYPE_POPUP:
+      return true;
+    case Browser::TYPE_APP:
+      return false;
+    case Browser::TYPE_APP_POPUP:
+      return false;
+    case Browser::TYPE_DEVTOOLS:
+      return false;
+    case Browser::TYPE_APP_PANEL:
+      return false;
+    case Browser::TYPE_NORMAL:
+    default:
+      return true;
   }
-  sync_api::ReadNode current_machine(trans);
-  int64 current_id = (current_machine.InitByClientTagLookup(syncable::SESSIONS,
-    GetCurrentMachineTag())) ? current_machine.GetId() : sync_api::kInvalidId;
+}
 
-  // Iterate through the nodes and populate the session model.
-  int64 id = root.GetFirstChildId();
-  while (id != sync_api::kInvalidId) {
-    sync_api::ReadNode sync_node(trans);
-    if (!sync_node.InitByIdLookup(id)) {
-      LOG(ERROR) << "Failed to fetch sync node for id " << id;
-      return false;
-    }
-    if (id != current_id) {
-      specifics.insert(specifics.end(), &sync_node.GetSessionSpecifics());
-    }
-    id = sync_node.GetSuccessorId();
+void SessionModelAssociator::ReassociateTabs(
+    const std::vector<TabContents*>& tabs) {
+  DCHECK(CalledOnValidThread());
+  for (std::vector<TabContents*>::const_iterator i = tabs.begin();
+       i != tabs.end();
+       ++i) {
+    ReassociateTab(**i);
   }
-  return true;
 }
 
-bool SessionModelAssociator::GetSessionData(
-    std::vector<ForeignSession*>* sessions) {
+void SessionModelAssociator::ReassociateTab(const TabContents& tab) {
   DCHECK(CalledOnValidThread());
+  if (!IsValidTab(tab))
+    return;
 
-  // Build vector of sessions from specifics data
-  for (std::vector<const sync_pb::SessionSpecifics*>::const_iterator i =
-    specifics_.begin(); i != specifics_.end(); ++i) {
-    // Only include sessions with open windows.
-    if ((*i)->session_window_size() > 0)
-      AppendForeignSessionFromSpecifics(*i, sessions);
+  int64 sync_id;
+  SessionID::id_type id = tab.controller().session_id().id();
+  if (tab.is_being_destroyed()) {
+    // This tab is closing.
+    TabLinksMap::iterator tab_iter = tab_map_.find(id);
+    if (tab_iter == tab_map_.end()) {
+      // We aren't tracking this tab (for example, sync setting page).
+      return;
+    }
+    tab_pool_.FreeTabNode(tab_iter->second.sync_id());
+    tab_map_.erase(tab_iter);
+    return;
   }
 
-  return true;
-}
-
-void SessionModelAssociator::AppendForeignSessionFromSpecifics(
-    const sync_pb::SessionSpecifics* specifics,
-    std::vector<ForeignSession*>* session) {
-  ForeignSession* foreign_session = new ForeignSession();
-  foreign_session->foreign_session_tag = specifics->session_tag();
-  session->insert(session->end(), foreign_session);
-  for (int i = 0; i < specifics->session_window_size(); i++) {
-    const sync_pb::SessionWindow* window = &specifics->session_window(i);
-    SessionWindow* session_window = new SessionWindow();
-    PopulateSessionWindowFromSpecifics(session_window, window);
-    foreign_session->windows.insert(
-        foreign_session->windows.end(), session_window);
+  TabLinksMap::const_iterator tablink = tab_map_.find(id);
+  if (tablink == tab_map_.end()) {
+    // This is a new tab, get a sync node for it.
+    sync_id = tab_pool_.GetFreeTabNode();
+  } else {
+    // This tab is already associated with a sync node, reuse it.
+    sync_id = tablink->second.sync_id();
   }
+  Associate(&tab, sync_id);
 }
 
-// Fills the given vector with foreign session windows to restore.
-void SessionModelAssociator::AppendForeignSessionWithID(int64 id,
-    std::vector<ForeignSession*>* session, sync_api::BaseTransaction* trans) {
-  if (id == sync_api::kInvalidId)
-    return;
-  sync_api::ReadNode node(trans);
-  if (!node.InitByIdLookup(id))
-    return;
-  const sync_pb::SessionSpecifics* ref = &node.GetSessionSpecifics();
-  AppendForeignSessionFromSpecifics(ref, session);
-}
+void SessionModelAssociator::Associate(const TabContents* tab, int64 sync_id) {
+  DCHECK(CalledOnValidThread());
+  SessionID::id_type session_id = tab->controller().session_id().id();
 
-SessionService* SessionModelAssociator::GetSessionService() {
-  DCHECK(sync_service_);
-  Profile* profile = sync_service_->profile();
-  DCHECK(profile);
-  SessionService* sessions_service = profile->GetSessionService();
-  DCHECK(sessions_service);
-  return sessions_service;
+  TabLinks t(sync_id, tab);
+  tab_map_[session_id] = t;
+
+  sync_api::WriteTransaction trans(
+      sync_service_->backend()->GetUserShareHandle());
+  WriteTabContentsToSyncModel(*tab, sync_id, &trans);
 }
 
-void SessionModelAssociator::InitializeCurrentMachineTag() {
-  sync_api::WriteTransaction trans(sync_service_->backend()->
-      GetUserShareHandle());
-  syncable::Directory* dir =
-      trans.GetWrappedWriteTrans()->directory();
+bool SessionModelAssociator::WriteTabContentsToSyncModel(
+    const TabContents& tab,
+    int64 sync_id,
+    sync_api::WriteTransaction* trans) {
+  DCHECK(CalledOnValidThread());
+  sync_api::WriteNode tab_node(trans);
+  if (!tab_node.InitByIdLookup(sync_id)) {
+    LOG(ERROR) << "Failed to look up tab node " << sync_id;
+    return false;
+  }
 
-  // TODO(zea): We need a better way of creating a machine tag. The directory
-  // kernel's cache_guid changes every time syncing is turned on and off. This
-  // will result in session's associated with stale machine tags persisting on
-  // the server since that tag will not be reused. Eventually this should
-  // become some string identifiable to the user. (Home, Work, Laptop, etc.)
-  // See issue 59672
-  current_machine_tag_ = "session_sync";
-  current_machine_tag_.append(dir->cache_guid());
-  VLOG(1) << "Creating machine tag: " << current_machine_tag_;
+  sync_pb::SessionSpecifics session_s;
+  session_s.set_session_tag(GetCurrentMachineTag());
+  sync_pb::SessionTab* tab_s = session_s.mutable_tab();
+
+  SessionID::id_type tab_id = tab.controller().session_id().id();
+  tab_s->set_tab_id(tab_id);
+  tab_s->set_window_id(tab.controller().window_id().id());
+  const int current_index = tab.controller().GetCurrentEntryIndex();
+  const int min_index = std::max(0,
+                                 current_index - max_sync_navigation_count);
+  const int max_index = std::min(current_index + max_sync_navigation_count,
+                                 tab.controller().entry_count());
+  const int pending_index = tab.controller().pending_entry_index();
+  Browser* browser = BrowserList::FindBrowserWithID(
+      tab.controller().window_id().id());
+  DCHECK(browser);
+  int index_in_window = browser->tabstrip_model()->GetWrapperIndex(&tab);
+  DCHECK(index_in_window != TabStripModel::kNoTab);
+  tab_s->set_pinned(browser->tabstrip_model()->IsTabPinned(index_in_window));
+  if (tab.extension_app())
+    tab_s->set_extension_app_id(tab.extension_app()->id());
+  for (int i = min_index; i < max_index; ++i) {
+    const NavigationEntry* entry = (i == pending_index) ?
+       tab.controller().pending_entry() : tab.controller().GetEntryAtIndex(i);
+    DCHECK(entry);
+    if (entry->virtual_url().is_valid()) {
+      if (i == max_index - 1) {
+        VLOG(1) << "Associating tab " << tab_id << " with sync id " << sync_id
+            << " and url " << entry->virtual_url().possibly_invalid_spec();
+      }
+      TabNavigation tab_nav;
+      tab_nav.SetFromNavigationEntry(*entry);
+      sync_pb::TabNavigation* nav_s = tab_s->add_navigation();
+      PopulateSessionSpecificsNavigation(&tab_nav, nav_s);
+    }
+  }
+  tab_s->set_current_navigation_index(current_index);
+
+  tab_node.SetSessionSpecifics(session_s);
+  return true;
 }
 
-// See PopulateSessionSpecificsTab for use.  May add functionality that includes
-// the state later.
+// Static
+// TODO(zea): perhaps sync state (scroll position, form entries, etc.) as well?
+// See http://crbug.com/67068.
 void SessionModelAssociator::PopulateSessionSpecificsNavigation(
-  const TabNavigation* navigation, sync_pb::TabNavigation* tab_navigation) {
+    const TabNavigation* navigation,
+    sync_pb::TabNavigation* tab_navigation) {
   tab_navigation->set_index(navigation->index());
   tab_navigation->set_virtual_url(navigation->virtual_url().spec());
   tab_navigation->set_referrer(navigation->referrer().spec());
@@ -334,125 +345,280 @@ void SessionModelAssociator::PopulateSessionSpecificsNavigation(
   }
 }
 
-// See PopulateSessionSpecificsWindow for use.
-void SessionModelAssociator::PopulateSessionSpecificsTab(
-  const SessionTab* tab, sync_pb::SessionTab* session_tab) {
-  session_tab->set_tab_visual_index(tab->tab_visual_index);
-  session_tab->set_current_navigation_index(
-      tab->current_navigation_index);
-  session_tab->set_pinned(tab->pinned);
-  session_tab->set_extension_app_id(tab->extension_app_id);
-  for (std::vector<TabNavigation>::const_iterator i3 =
-      tab->navigations.begin(); i3 != tab->navigations.end(); ++i3) {
-    const TabNavigation navigation = *i3;
-    sync_pb::TabNavigation* tab_navigation =
-        session_tab->add_navigation();
-    PopulateSessionSpecificsNavigation(&navigation, tab_navigation);
-  }
+void SessionModelAssociator::Disassociate(int64 sync_id) {
+  DCHECK(CalledOnValidThread());
+  NOTIMPLEMENTED();
+  // TODO(zea): we will need this once we support deleting foreign sessions.
 }
 
-// Called when populating session specifics to send to the sync model, called
-// when associating models, or updating the sync model.
-void SessionModelAssociator::PopulateSessionSpecificsWindow(
-  const SessionWindow* window, sync_pb::SessionWindow* session_window) {
-    session_window->set_selected_tab_index(window->selected_tab_index);
-    if (window->type == 1) {
-      session_window->set_browser_type(
-        sync_pb::SessionWindow_BrowserType_TYPE_NORMAL);
-    } else {
-      session_window->set_browser_type(
-        sync_pb::SessionWindow_BrowserType_TYPE_POPUP);
+bool SessionModelAssociator::AssociateModels() {
+  DCHECK(CalledOnValidThread());
+
+  // Ensure that we disassociated properly, otherwise memory might leak.
+  DCHECK(foreign_session_tracker_.empty());
+  DCHECK_EQ(0U, tab_pool_.capacity());
+
+  local_session_syncid_ = sync_api::kInvalidId;
+
+  // Read any available foreign sessions and load any session data we may have.
+  // If we don't have any local session data in the db, create a header node.
+  {
+    sync_api::WriteTransaction trans(
+        sync_service_->backend()->GetUserShareHandle());
+
+    sync_api::ReadNode root(&trans);
+    if (!root.InitByTagLookup(kSessionsTag)) {
+      LOG(ERROR) << kNoSessionsFolderError;
+      return false;
     }
-    for (std::vector<SessionTab*>::const_iterator i2 = window->tabs.begin();
-        i2 != window->tabs.end(); ++i2) {
-      const SessionTab* tab = *i2;
-      if (tab->navigations.at(tab->current_navigation_index).virtual_url() ==
-        GURL(chrome::kChromeUINewTabURL)) {
-        continue;
+
+    // Make sure we have a machine tag.
+    if (current_machine_tag_.empty())
+      InitializeCurrentMachineTag(&trans);
+
+    UpdateAssociationsFromSyncModel(root, &trans);
+
+    if (local_session_syncid_ == sync_api::kInvalidId) {
+      // The sync db didn't have a header node for us, we need to create one.
+      sync_api::WriteNode write_node(&trans);
+      if (!write_node.InitUniqueByCreation(syncable::SESSIONS, root,
+          current_machine_tag_)) {
+        LOG(ERROR) << "Failed to create sessions header sync node.";
+        return false;
       }
-      sync_pb::SessionTab* session_tab = session_window->add_session_tab();
-      PopulateSessionSpecificsTab(tab, session_tab);
+      write_node.SetTitle(UTF8ToWide(current_machine_tag_));
+      local_session_syncid_ = write_node.GetId();
     }
+  }
+
+  // Check if anything has changed on the client side.
+  UpdateSyncModelDataFromClient();
+
+  VLOG(1) << "Session models associated.";
+
+  return true;
 }
 
-bool SessionModelAssociator::WindowHasNoTabsToSync(
-    const SessionWindow* window) {
-  int num_populated = 0;
-  for (std::vector<SessionTab*>::const_iterator i = window->tabs.begin();
-      i != window->tabs.end(); ++i) {
-    const SessionTab* tab = *i;
-    if (tab->navigations.at(tab->current_navigation_index).virtual_url() ==
-        GURL(chrome::kChromeUINewTabURL)) {
-      continue;
+bool SessionModelAssociator::DisassociateModels() {
+  DCHECK(CalledOnValidThread());
+  foreign_session_tracker_.clear();
+  tab_map_.clear();
+  tab_pool_.clear();
+  local_session_syncid_ = sync_api::kInvalidId;
+
+  // There is no local model stored with which to disassociate, just notify
+  // foreign session handlers.
+  NotificationService::current()->Notify(
+      NotificationType::FOREIGN_SESSION_DISABLED,
+      NotificationService::AllSources(),
+      NotificationService::NoDetails());
+  return true;
+}
+
+void SessionModelAssociator::InitializeCurrentMachineTag(
+    sync_api::WriteTransaction* trans) {
+  DCHECK(CalledOnValidThread());
+  syncable::Directory* dir = trans->GetWrappedWriteTrans()->directory();
+
+  // TODO(zea): We need a better way of creating a machine tag. The directory
+  // kernel's cache_guid changes every time syncing is turned on and off. This
+  // will result in session's associated with stale machine tags persisting on
+  // the server since that tag will not be reused. Eventually this should
+  // become some string identifiable to the user. (Home, Work, Laptop, etc.)
+  // See issue at http://crbug.com/59672
+  current_machine_tag_ = "session_sync";
+  current_machine_tag_.append(dir->cache_guid());
+  VLOG(1) << "Creating machine tag: " << current_machine_tag_;
+  tab_pool_.set_machine_tag(current_machine_tag_);
+}
+
+bool SessionModelAssociator::UpdateAssociationsFromSyncModel(
+    const sync_api::ReadNode& root,
+    const sync_api::BaseTransaction* trans) {
+  DCHECK(CalledOnValidThread());
+
+  // Iterate through the nodes and associate any foreign sessions.
+  int64 id = root.GetFirstChildId();
+  while (id != sync_api::kInvalidId) {
+    sync_api::ReadNode sync_node(trans);
+    if (!sync_node.InitByIdLookup(id)) {
+      LOG(ERROR) << "Failed to fetch sync node for id " << id;
+      return false;
     }
-    num_populated++;
+
+    const sync_pb::SessionSpecifics& specifics =
+        sync_node.GetSessionSpecifics();
+    const int64 modification_time = sync_node.GetModificationTime();
+    if (specifics.session_tag() != GetCurrentMachineTag()) {
+      if (!AssociateForeignSpecifics(specifics, modification_time)) {
+        return false;
+      }
+    } else if (id != local_session_syncid_) {
+      // This is previously stored local session information.
+      if (specifics.has_header()) {
+        DCHECK_EQ(sync_api::kInvalidId, local_session_syncid_);
+
+        // This is our previous header node, reuse it.
+        local_session_syncid_ = id;
+      } else {
+        DCHECK(specifics.has_tab());
+
+        // This is a tab node. We want to track these to reuse them in our free
+        // tab node pool. They will be overwritten eventually, so need to do
+        // anything else.
+        tab_pool_.AddTabNode(id);
+      }
+    }
+
+    id = sync_node.GetSuccessorId();
   }
-  if (num_populated == 0)
-    return true;
-  return false;
+
+  // After updating from sync model all tabid's should be free.
+  DCHECK(tab_pool_.full());
+
+  return true;
 }
 
-void SessionModelAssociator::OnGotSession(int handle,
-    std::vector<SessionWindow*>* windows) {
-  sync_pb::SessionSpecifics specifics;
-  // Set the tag, then iterate through the vector of windows, extracting the
-  // window data, along with the tabs data and tab navigation data to populate
-  // the session specifics.
-  specifics.set_session_tag(GetCurrentMachineTag());
-  FillSpecificsFromSessions(windows, &specifics);
-  bool has_nodes = false;
-  if (!SyncModelHasUserCreatedNodes(&has_nodes))
-    return;
-  if (specifics.session_window_size() == 0 && has_nodes)
-    return;
-  sync_api::WriteTransaction trans(
-      sync_service_->backend()->GetUserShareHandle());
-  sync_api::ReadNode root(&trans);
-  if (!root.InitByTagLookup(kSessionsTag)) {
-    LOG(ERROR) << kNoSessionsFolderError;
-    return;
+bool SessionModelAssociator::AssociateForeignSpecifics(
+    const sync_pb::SessionSpecifics& specifics,
+    const int64 modification_time) {
+  DCHECK(CalledOnValidThread());
+  std::string foreign_session_tag = specifics.session_tag();
+  DCHECK(foreign_session_tag != GetCurrentMachineTag() ||
+         sync_service_->cros_user() == "test user");  // For tests.
+
+  if (specifics.has_header()) {
+    // Read in the header data for this foreign session.
+    // Header data contains window information and ordered tab id's for each
+    // window.
+
+    // Load (or create) the ForeignSession object for this client.
+    ForeignSession* foreign_session =
+        foreign_session_tracker_.GetForeignSession(foreign_session_tag);
+
+    const sync_pb::SessionHeader& header = specifics.header();
+    foreign_session->windows.reserve(header.window_size());
+    VLOG(1) << "Associating " << foreign_session_tag << " with " <<
+        header.window_size() << " windows.";
+    size_t i;
+    for (i = 0; i < static_cast<size_t>(header.window_size()); ++i) {
+      if (i >= foreign_session->windows.size()) {
+        // This a new window, create it.
+        foreign_session->windows.push_back(new SessionWindow());
+      }
+      const sync_pb::SessionWindow& window_s = header.window(i);
+      PopulateSessionWindowFromSpecifics(foreign_session_tag,
+                                         window_s,
+                                         modification_time,
+                                         foreign_session->windows[i],
+                                         &foreign_session_tracker_);
+    }
+    // Remove any remaining windows (in case windows were closed)
+    for (; i < foreign_session->windows.size(); ++i) {
+      delete foreign_session->windows[i];
+    }
+    foreign_session->windows.resize(header.window_size());
+  } else if (specifics.has_tab()) {
+    const sync_pb::SessionTab& tab_s = specifics.tab();
+    SessionID::id_type tab_id = tab_s.tab_id();
+    SessionTab* tab =
+        foreign_session_tracker_.GetSessionTab(foreign_session_tag,
+                                               tab_id,
+                                               false);
+    PopulateSessionTabFromSpecifics(tab_s, modification_time, tab);
+  } else {
+    NOTREACHED();
+    return false;
   }
-  UpdateSyncModel(&specifics, &trans, &root);
+
+  return true;
 }
 
-void SessionModelAssociator::FillSpecificsFromSessions(
-    std::vector<SessionWindow*>* windows,
-    sync_pb::SessionSpecifics* session) {
-  for (std::vector<SessionWindow*>::const_iterator i = windows->begin();
-      i != windows->end(); ++i) {
-    const SessionWindow* window = *i;
-    if (WindowHasNoTabsToSync(window)) {
-      continue;
+void SessionModelAssociator::DisassociateForeignSession(
+    const std::string& foreign_session_tag) {
+  DCHECK(CalledOnValidThread());
+  foreign_session_tracker_.DeleteForeignSession(foreign_session_tag);
+}
+
+// Static
+void SessionModelAssociator::PopulateSessionWindowFromSpecifics(
+    std::string foreign_session_tag,
+    const sync_pb::SessionWindow& specifics,
+    int64 mtime,
+    SessionWindow* session_window,
+    ForeignSessionTracker* tracker) {
+  if (specifics.has_window_id())
+    session_window->window_id.set_id(specifics.window_id());
+  if (specifics.has_selected_tab_index())
+    session_window->selected_tab_index = specifics.selected_tab_index();
+  if (specifics.has_browser_type()) {
+    if (specifics.browser_type() ==
+        sync_pb::SessionWindow_BrowserType_TYPE_NORMAL) {
+      session_window->type = 1;
+    } else {
+      session_window->type = 2;
     }
-    sync_pb::SessionWindow* session_window = session->add_session_window();
-    PopulateSessionSpecificsWindow(window, session_window);
+  }
+  session_window->timestamp = base::Time::FromInternalValue(mtime);
+  session_window->tabs.resize(specifics.tab_size());
+  for (int i = 0; i < specifics.tab_size(); i++) {
+    SessionID::id_type tab_id = specifics.tab(i);
+    session_window->tabs[i] =
+        tracker->GetSessionTab(foreign_session_tag, tab_id, true);
   }
 }
 
+// Static
+void SessionModelAssociator::PopulateSessionTabFromSpecifics(
+    const sync_pb::SessionTab& specifics,
+    const int64 mtime,
+    SessionTab* tab) {
+  if (specifics.has_tab_id())
+    tab->tab_id.set_id(specifics.tab_id());
+  if (specifics.has_window_id())
+    tab->window_id.set_id(specifics.window_id());
+  if (specifics.has_tab_visual_index())
+    tab->tab_visual_index = specifics.tab_visual_index();
+  if (specifics.has_current_navigation_index())
+    tab->current_navigation_index = specifics.current_navigation_index();
+  if (specifics.has_pinned())
+    tab->pinned = specifics.pinned();
+  if (specifics.has_extension_app_id())
+    tab->extension_app_id = specifics.extension_app_id();
+  tab->timestamp = base::Time::FromInternalValue(mtime);
+  tab->navigations.clear();  // In case we are reusing a previous SessionTab.
+  for (int i = 0; i < specifics.navigation_size(); i++) {
+    AppendSessionTabNavigation(specifics.navigation(i), &tab->navigations);
+  }
+}
+
+// Static
 void SessionModelAssociator::AppendSessionTabNavigation(
-    std::vector<TabNavigation>* navigations,
-    const sync_pb::TabNavigation* navigation) {
+    const sync_pb::TabNavigation& specifics,
+    std::vector<TabNavigation>* navigations) {
   int index = 0;
   GURL virtual_url;
   GURL referrer;
   string16 title;
   std::string state;
   PageTransition::Type transition(PageTransition::LINK);
-  if (navigation->has_index())
-    index = navigation->index();
-  if (navigation->has_virtual_url()) {
-    GURL gurl(navigation->virtual_url());
+  if (specifics.has_index())
+    index = specifics.index();
+  if (specifics.has_virtual_url()) {
+    GURL gurl(specifics.virtual_url());
     virtual_url = gurl;
   }
-  if (navigation->has_referrer()) {
-    GURL gurl(navigation->referrer());
+  if (specifics.has_referrer()) {
+    GURL gurl(specifics.referrer());
     referrer = gurl;
   }
-  if (navigation->has_title())
-    title = UTF8ToUTF16(navigation->title());
-  if (navigation->has_page_transition() ||
-      navigation->has_navigation_qualifier()) {
-    switch (navigation->page_transition()) {
+  if (specifics.has_title())
+    title = UTF8ToUTF16(specifics.title());
+  if (specifics.has_state())
+    state = specifics.state();
+  if (specifics.has_page_transition() ||
+      specifics.has_navigation_qualifier()) {
+    switch (specifics.page_transition()) {
       case sync_pb::TabNavigation_PageTransition_LINK:
         transition = PageTransition::LINK;
         break;
@@ -493,7 +659,7 @@ void SessionModelAssociator::AppendSessionTabNavigation(
         transition = PageTransition::CHAIN_END;
         break;
       default:
-        switch (navigation->navigation_qualifier()) {
+        switch (specifics.navigation_qualifier()) {
           case sync_pb::
               TabNavigation_PageTransitionQualifier_CLIENT_REDIRECT:
             transition = PageTransition::CLIENT_REDIRECT;
@@ -512,67 +678,291 @@ void SessionModelAssociator::AppendSessionTabNavigation(
   navigations->insert(navigations->end(), tab_navigation);
 }
 
-void SessionModelAssociator::PopulateSessionTabFromSpecifics(
-    SessionTab* session_tab,
-    const sync_pb::SessionTab* tab, SessionID id) {
-  session_tab->window_id = id;
-  SessionID tabID;
-  session_tab->tab_id = tabID;
-  if (tab->has_tab_visual_index())
-    session_tab->tab_visual_index = tab->tab_visual_index();
-  if (tab->has_current_navigation_index()) {
-    session_tab->current_navigation_index =
-    tab->current_navigation_index();
+void SessionModelAssociator::UpdateSyncModelDataFromClient() {
+  DCHECK(CalledOnValidThread());
+  // TODO(zea): the logic for determining if we want to sync and the loading of
+  // the previous session should go here. We can probably reuse the code for
+  // loading the current session from the old session implementation.
+  // SessionService::SessionCallback* callback =
+  //     NewCallback(this, &SessionModelAssociator::OnGotSession);
+  // GetSessionService()->GetCurrentSession(&consumer_, callback);
+
+  // Associate all open windows and their tabs.
+  ReassociateWindows(true);
+}
+
+SessionModelAssociator::TabNodePool::TabNodePool(
+    ProfileSyncService* sync_service)
+    : tab_pool_fp_(-1),
+      sync_service_(sync_service) {
+}
+
+void SessionModelAssociator::TabNodePool::AddTabNode(int64 sync_id) {
+  tab_syncid_pool_.resize(tab_syncid_pool_.size() + 1);
+  tab_syncid_pool_[static_cast<size_t>(++tab_pool_fp_)] = sync_id;
+}
+
+int64 SessionModelAssociator::TabNodePool::GetFreeTabNode() {
+  DCHECK_GT(machine_tag_.length(), 0U);
+  if (tab_pool_fp_ == -1) {
+    // Tab pool has no free nodes, allocate new one.
+    sync_api::WriteTransaction trans(
+        sync_service_->backend()->GetUserShareHandle());
+    sync_api::ReadNode root(&trans);
+    if (!root.InitByTagLookup(kSessionsTag)) {
+      LOG(ERROR) << kNoSessionsFolderError;
+      return 0;
+    }
+    size_t tab_node_id = tab_syncid_pool_.size();
+    std::string tab_node_tag = TabIdToTag(machine_tag_, tab_node_id);
+    sync_api::WriteNode tab_node(&trans);
+    if (!tab_node.InitUniqueByCreation(syncable::SESSIONS, root,
+                                       tab_node_tag)) {
+      LOG(ERROR) << "Could not create new node!";
+      return -1;
+    }
+    tab_node.SetTitle(UTF8ToWide(tab_node_tag));
+
+    // Grow the pool by 1 since we created a new node. We don't actually need
+    // to put the node's id in the pool now, since the pool is still empty.
+    // The id will be added when that tab is closed and the node is freed.
+    tab_syncid_pool_.resize(tab_node_id + 1);
+    VLOG(1) << "Adding sync node " << tab_node.GetId() << " to tab syncid pool";
+    return tab_node.GetId();
+  } else {
+    // There are nodes available, grab next free and decrement free pointer.
+    return tab_syncid_pool_[static_cast<size_t>(tab_pool_fp_--)];
   }
-  if (tab->has_pinned())
-    session_tab->pinned = tab->pinned();
-  if (tab->has_extension_app_id())
-    session_tab->extension_app_id = tab->extension_app_id();
-  for (int i3 = 0; i3 < tab->navigation_size(); i3++) {
-    const sync_pb::TabNavigation* navigation = &tab->navigation(i3);
-    AppendSessionTabNavigation(&session_tab->navigations, navigation);
+}
+
+void SessionModelAssociator::TabNodePool::FreeTabNode(int64 sync_id) {
+  // Pool size should always match # of free tab nodes.
+  DCHECK_LT(tab_pool_fp_, static_cast<int64>(tab_syncid_pool_.size()));
+  tab_syncid_pool_[static_cast<size_t>(++tab_pool_fp_)] = sync_id;
+}
+
+bool SessionModelAssociator::GetAllForeignSessions(
+    std::vector<const ForeignSession*>* sessions) {
+  DCHECK(CalledOnValidThread());
+  return foreign_session_tracker_.LookupAllForeignSessions(sessions);
+}
+
+bool SessionModelAssociator::GetForeignSession(
+    const std::string& tag,
+    std::vector<SessionWindow*>* windows) {
+  DCHECK(CalledOnValidThread());
+  return foreign_session_tracker_.LookupSessionWindows(tag, windows);
+}
+
+bool SessionModelAssociator::GetForeignTab(
+    const std::string& tag,
+    const SessionID::id_type tab_id,
+    const SessionTab** tab) {
+  DCHECK(CalledOnValidThread());
+  return foreign_session_tracker_.LookupSessionTab(tag, tab_id, tab);
+}
+
+// Static
+bool SessionModelAssociator::SessionWindowHasNoTabsToSync(
+    const SessionWindow& window) {
+  int num_populated = 0;
+  for (std::vector<SessionTab*>::const_iterator i = window.tabs.begin();
+      i != window.tabs.end(); ++i) {
+    const SessionTab* tab = *i;
+    if (IsValidSessionTab(*tab))
+      num_populated++;
   }
+  if (num_populated == 0)
+    return true;
+  return false;
 }
 
-void SessionModelAssociator::PopulateSessionWindowFromSpecifics(
-    SessionWindow* session_window, const sync_pb::SessionWindow* window) {
-  SessionID id;
-  session_window->window_id = id;
-  if (window->has_selected_tab_index())
-    session_window->selected_tab_index = window->selected_tab_index();
-  if (window->has_browser_type()) {
-    if (window->browser_type() ==
-        sync_pb::SessionWindow_BrowserType_TYPE_NORMAL) {
-      session_window->type = 1;
-    } else {
-      session_window->type = 2;
+// Valid local tab?
+bool SessionModelAssociator::IsValidTab(const TabContents& tab) {
+  DCHECK(CalledOnValidThread());
+  if ((tab.profile() == sync_service_->profile() ||
+       sync_service_->profile() == NULL)) {
+    const NavigationEntry* entry = tab.controller().GetActiveEntry();
+    if (!entry)
+      return false;
+    if (entry->virtual_url().is_valid() &&
+        (entry->virtual_url() != GURL(chrome::kChromeUINewTabURL) ||
+         tab.controller().entry_count() > 1)) {
+      return true;
     }
   }
-  for (int i = 0; i < window->session_tab_size(); i++) {
-    const sync_pb::SessionTab& tab = window->session_tab(i);
-    SessionTab* session_tab = new SessionTab();
-    PopulateSessionTabFromSpecifics(session_tab, &tab, id);
-    session_window->tabs.insert(session_window->tabs.end(), session_tab);
+  return false;
+}
+
+// Static
+bool SessionModelAssociator::IsValidSessionTab(const SessionTab& tab) {
+  if (tab.navigations.empty())
+    return false;
+  int selected_index = tab.current_navigation_index;
+  selected_index = std::max(
+      0,
+      std::min(selected_index,
+          static_cast<int>(tab.navigations.size() - 1)));
+  if (selected_index == 0 &&
+      tab.navigations.size() == 1 &&
+      tab.navigations.at(selected_index).virtual_url() ==
+          GURL(chrome::kChromeUINewTabURL)) {
+    // This is a new tab with no further history, skip.
+    return false;
+  }
+  return true;
+}
+
+// ==========================================================================
+// The following methods are not currently used but will likely become useful
+// if we choose to sync the previous browser session.
+
+SessionService* SessionModelAssociator::GetSessionService() {
+  DCHECK(CalledOnValidThread());
+  DCHECK(sync_service_);
+  Profile* profile = sync_service_->profile();
+  DCHECK(profile);
+  SessionService* sessions_service = profile->GetSessionService();
+  DCHECK(sessions_service);
+  return sessions_service;
+}
+
+void SessionModelAssociator::OnGotSession(
+    int handle,
+    std::vector<SessionWindow*>* windows) {
+  DCHECK(CalledOnValidThread());
+  DCHECK(local_session_syncid_);
+
+  sync_pb::SessionSpecifics specifics;
+  specifics.set_session_tag(GetCurrentMachineTag());
+  sync_pb::SessionHeader* header_s = specifics.mutable_header();
+  PopulateSessionSpecificsHeader(*windows, header_s);
+
+  sync_api::WriteTransaction trans(
+      sync_service_->backend()->GetUserShareHandle());
+  sync_api::ReadNode root(&trans);
+  if (!root.InitByTagLookup(kSessionsTag)) {
+    LOG(ERROR) << kNoSessionsFolderError;
+    return;
+  }
+
+  sync_api::WriteNode header_node(&trans);
+  if (!header_node.InitByIdLookup(local_session_syncid_)) {
+    LOG(ERROR) << "Failed to load local session header node.";
+    return;
+  }
+
+  header_node.SetSessionSpecifics(specifics);
+}
+
+void SessionModelAssociator::PopulateSessionSpecificsHeader(
+    const std::vector<SessionWindow*>& windows,
+    sync_pb::SessionHeader* header_s) {
+  DCHECK(CalledOnValidThread());
+
+  // Iterate through the vector of windows, extracting the window data, along
+  // with the tab data to populate the session specifics.
+  for (size_t i = 0; i < windows.size(); ++i) {
+    if (SessionWindowHasNoTabsToSync(*(windows[i])))
+      continue;
+    sync_pb::SessionWindow* window_s = header_s->add_window();
+    PopulateSessionSpecificsWindow(*(windows[i]), window_s);
+    if (!SyncLocalWindowToSyncModel(*(windows[i])))
+      return;
+  }
+}
+
+// Called when populating session specifics to send to the sync model, called
+// when associating models, or updating the sync model.
+void SessionModelAssociator::PopulateSessionSpecificsWindow(
+    const SessionWindow& window,
+    sync_pb::SessionWindow* session_window) {
+  DCHECK(CalledOnValidThread());
+  session_window->set_window_id(window.window_id.id());
+  session_window->set_selected_tab_index(window.selected_tab_index);
+  if (window.type == Browser::TYPE_NORMAL) {
+    session_window->set_browser_type(
+      sync_pb::SessionWindow_BrowserType_TYPE_NORMAL);
+  } else if (window.type == Browser::TYPE_POPUP) {
+    session_window->set_browser_type(
+      sync_pb::SessionWindow_BrowserType_TYPE_POPUP);
+  } else {
+    // ignore
+    LOG(WARNING) << "Session Sync unable to handle windows of type" <<
+        window.type;
+    return;
+  }
+  for (std::vector<SessionTab*>::const_iterator i = window.tabs.begin();
+      i != window.tabs.end(); ++i) {
+    const SessionTab* tab = *i;
+    if (!IsValidSessionTab(*tab))
+      continue;
+    session_window->add_tab(tab->tab_id.id());
   }
 }
 
-bool SessionModelAssociator::UpdateSyncModel(
-    sync_pb::SessionSpecifics* session_data,
-    sync_api::WriteTransaction* trans,
-    const sync_api::ReadNode* root) {
-  const std::string id = session_data->session_tag();
-  sync_api::WriteNode write_node(trans);
-  if (!write_node.InitByClientTagLookup(syncable::SESSIONS, id)) {
-    sync_api::WriteNode create_node(trans);
-    if (!create_node.InitUniqueByCreation(syncable::SESSIONS, *root, id)) {
-      LOG(ERROR) << "Could not create node for session " << id;
+bool SessionModelAssociator::SyncLocalWindowToSyncModel(
+    const SessionWindow& window) {
+  DCHECK(CalledOnValidThread());
+  DCHECK(tab_map_.empty());
+  for (size_t i = 0; i < window.tabs.size(); ++i) {
+    SessionTab* tab = window.tabs[i];
+    int64 id = tab_pool_.GetFreeTabNode();
+    if (id == -1) {
+      LOG(ERROR) << "Failed to find/generate free sync node for tab.";
       return false;
     }
-    create_node.SetSessionSpecifics(*session_data);
-    return true;
+
+    sync_api::WriteTransaction trans(
+        sync_service_->backend()->GetUserShareHandle());
+    if (!WriteSessionTabToSyncModel(*tab, id, &trans)) {
+      return false;
+    }
+
+    TabLinks t(id, tab);
+    tab_map_[tab->tab_id.id()] = t;
   }
-  write_node.SetSessionSpecifics(*session_data);
   return true;
 }
 
+bool SessionModelAssociator::WriteSessionTabToSyncModel(
+    const SessionTab& tab,
+    const int64 sync_id,
+    sync_api::WriteTransaction* trans) {
+  DCHECK(CalledOnValidThread());
+  sync_api::WriteNode tab_node(trans);
+  if (!tab_node.InitByIdLookup(sync_id)) {
+    LOG(ERROR) << "Failed to look up tab node " << sync_id;
+    return false;
+  }
+
+  sync_pb::SessionSpecifics specifics;
+  specifics.set_session_tag(GetCurrentMachineTag());
+  sync_pb::SessionTab* tab_s = specifics.mutable_tab();
+  PopulateSessionSpecificsTab(tab, tab_s);
+  tab_node.SetSessionSpecifics(specifics);
+  return true;
+}
+
+// See PopulateSessionSpecificsWindow for use.
+void SessionModelAssociator::PopulateSessionSpecificsTab(
+    const SessionTab& tab,
+    sync_pb::SessionTab* session_tab) {
+  DCHECK(CalledOnValidThread());
+  session_tab->set_tab_id(tab.tab_id.id());
+  session_tab->set_window_id(tab.window_id.id());
+  session_tab->set_tab_visual_index(tab.tab_visual_index);
+  session_tab->set_current_navigation_index(
+      tab.current_navigation_index);
+  session_tab->set_pinned(tab.pinned);
+  session_tab->set_extension_app_id(tab.extension_app_id);
+  for (std::vector<TabNavigation>::const_iterator i =
+      tab.navigations.begin(); i != tab.navigations.end(); ++i) {
+    const TabNavigation navigation = *i;
+    sync_pb::TabNavigation* tab_navigation =
+        session_tab->add_navigation();
+    PopulateSessionSpecificsNavigation(&navigation, tab_navigation);
+  }
+}
+
 }  // namespace browser_sync
diff --git a/chrome/browser/sync/glue/session_model_associator.h b/chrome/browser/sync/glue/session_model_associator.h
index 502af18..cff376f 100644
--- a/chrome/browser/sync/glue/session_model_associator.h
+++ b/chrome/browser/sync/glue/session_model_associator.h
@@ -6,6 +6,7 @@
 #define CHROME_BROWSER_SYNC_GLUE_SESSION_MODEL_ASSOCIATOR_H_
 #pragma once
 
+#include <map>
 #include <string>
 #include <vector>
 
@@ -13,12 +14,19 @@
 #include "base/gtest_prod_util.h"
 #include "base/observer_list.h"
 #include "base/scoped_vector.h"
+#include "base/string_util.h"
+#include "base/threading/non_thread_safe.h"
+#include "base/utf_string_conversions.h"
+#include "chrome/browser/browser_window.h"
+#include "chrome/browser/sessions/session_id.h"
 #include "chrome/browser/sessions/session_service.h"
 #include "chrome/browser/sessions/session_types.h"
 #include "chrome/browser/sync/engine/syncapi.h"
+#include "chrome/browser/sync/glue/foreign_session_tracker.h"
 #include "chrome/browser/sync/glue/model_associator.h"
 #include "chrome/browser/sync/protocol/session_specifics.pb.h"
 #include "chrome/browser/sync/syncable/model_type.h"
+#include "chrome/browser/tab_contents/tab_contents.h"
 #include "chrome/common/notification_registrar.h"
 
 class Profile;
@@ -40,59 +48,76 @@ static const char kSessionsTag[] = "google_chrome_sessions";
 
 // Contains all logic for associating the Chrome sessions model and
 // the sync sessions model.
-// In the case of sessions, our local model is nothing but a buffer (specifics_)
-// that gets overwritten everytime there is an update. From it, we build a new
-// foreign session windows list each time |GetSessionData| is called by the
-// ForeignSessionHandler.
-class SessionModelAssociator : public PerDataTypeAssociatorInterface<
-    sync_pb::SessionSpecifics, std::string>, public NonThreadSafe {
+class SessionModelAssociator
+    : public PerDataTypeAssociatorInterface<TabContents, size_t>,
+      public base::NonThreadSafe {
  public:
-
   // Does not take ownership of sync_service.
   explicit SessionModelAssociator(ProfileSyncService* sync_service);
   virtual ~SessionModelAssociator();
 
+  // The has_nodes out parameter is set to true if the sync model has
+  // nodes other than the permanent tagged nodes.  The method may
+  // return false if an error occurred.
+  virtual bool SyncModelHasUserCreatedNodes(bool* has_nodes);
+
   // AssociatorInterface and PerDataTypeAssociator Interface implementation.
   virtual void AbortAssociation() {
-    // No implementation needed, this associator runs on the main
-    // thread.
-  }
-
-  // Dummy method, we do everything all-at-once in UpdateFromSyncModel.
-  virtual void Associate(const sync_pb::SessionSpecifics* specifics,
-    int64 sync_id) {
+    // No implementation needed, this associator runs on the main thread.
   }
 
-  // Updates the sync model with the local client data. (calls
-  // UpdateFromSyncModel)
-  virtual bool AssociateModels();
+  // Returns sync id for the given chrome model id.
+  // Returns sync_api::kInvalidId if the sync node is not found for the given
+  // chrome id.
+  virtual int64 GetSyncIdFromChromeId(const size_t& id);
 
-  // The has_nodes out parameter is set to true if the chrome model
-  // has user-created nodes.  The method may return false if an error
-  // occurred.
-  virtual bool ChromeModelHasUserCreatedNodes(bool* has_nodes);
+  // Returns sync id for the given session tag.
+  // Returns sync_api::kInvalidId if the sync node is not found for the given
+  // tag
+  virtual int64 GetSyncIdFromSessionTag(const std::string& tag);
 
-  // Dummy method, we do everything all-at-once in UpdateFromSyncModel.
-  virtual void Disassociate(int64 sync_id) {
+  // Not used.
+  virtual const TabContents* GetChromeNodeFromSyncId(int64 sync_id) {
+    NOTREACHED();
+    return NULL;
   }
 
-  // Clear specifics_ buffer and notify foreign session handlers.
-  virtual bool DisassociateModels();
-
-  // Returns the chrome session specifics for the given sync id.
-  // Returns NULL if no specifics are found for the given sync id.
-  virtual const sync_pb::SessionSpecifics* GetChromeNodeFromSyncId(
-    int64 sync_id);
-
-  // Returns whether a node with the given permanent tag was found and update
-  // |sync_id| with that node's id.
-  virtual bool GetSyncIdForTaggedNode(const std::string* tag, int64* sync_id);
-
-  // Returns sync id for the given chrome model id.
-  // Returns sync_api::kInvalidId if the sync node is not found for the given
-  // chrome id.
-  virtual int64 GetSyncIdFromChromeId(const std::string& id);
+  // Not used.
+  bool InitSyncNodeFromChromeId(const size_t& id,
+                                sync_api::BaseNode* sync_node) {
+    NOTREACHED();
+    return false;
+  }
 
+  // Resync local window information. Updates the local sessions header node
+  // with the status of open windows and the order of tabs they contain. Should
+  // only be called for changes that affect a window, not a change within a
+  // single tab.
+  //
+  // If |reload_tabs| is true, will also resync all tabs (same as calling
+  // ReassociateTabs with a vector of all tabs).
+  void ReassociateWindows(bool reload_tabs);
+
+  // Loads and reassociates the local tabs referenced in |tabs|.
+  void ReassociateTabs(const std::vector<TabContents*>& tabs);
+
+  // Reassociates a single tab with the sync model. Will check if the tab
+  // already is associated with a sync node and allocate one if necessary.
+  void ReassociateTab(const TabContents& tab);
+
+  // Associate a local tab and it's sync node. Will overwrite the contents of
+  // the sync node with new specifics built from the tab.
+  virtual void Associate(const TabContents* tab, int64 sync_id);
+
+  // Looks up the specified sync node, and marks that tab as closed, then marks
+  // the node as free and deletes association.
+  virtual void Disassociate(int64 sync_id);
+
+  // Load any foreign session info stored in sync db and update the sync db
+  // with local client data. Processes/reuses any sync nodes owned by this
+  // client and creates any further sync nodes needed to store local header and
+  // tab info.
+  virtual bool AssociateModels();
 
   // Initializes the given sync node from the given chrome node id.
   // Returns false if no sync node was found for the given chrome node id or
@@ -100,46 +125,53 @@ class SessionModelAssociator : public PerDataTypeAssociatorInterface<
   virtual bool InitSyncNodeFromChromeId(const std::string& id,
                                         sync_api::BaseNode* sync_node);
 
-  // The has_nodes out parameter is set to true if the sync model has
-  // nodes other than the permanent tagged nodes.  The method may
-  // return false if an error occurred.
-  virtual bool SyncModelHasUserCreatedNodes(bool* has_nodes);
+  // Clear local sync data buffers. Does not delete sync nodes to avoid
+  // tombstones. TODO(zea): way to eventually delete orphaned nodes.
+  virtual bool DisassociateModels();
 
   // Returns the tag used to uniquely identify this machine's session in the
   // sync model.
-  std::string GetCurrentMachineTag();
+  inline const std::string& GetCurrentMachineTag() {
+    DCHECK(!current_machine_tag_.empty());
+    return current_machine_tag_;
+  }
 
-  // Updates the server data based upon the current client session.  If no node
-  // corresponding to this machine exists in the sync model, one is created.
-  void UpdateSyncModelDataFromClient();
+  // Load and associate window and tab data for a foreign session
+  bool AssociateForeignSpecifics(const sync_pb::SessionSpecifics& specifics,
+                                 int64 modification_time);
 
-  // Pulls the current sync model from the sync database and returns true upon
-  // update of the client model. Called by SessionChangeProcessor.
-  // Note that the specifics_ vector is reset and built from scratch each time.
-  bool UpdateFromSyncModel(const sync_api::BaseTransaction* trans);
+  // Removes a foreign session from our internal bookkeeping.
+  void DisassociateForeignSession(const std::string& foreign_session_tag);
+
+  // Builds a list of all foreign sessions.
+  // Caller does NOT own ForeignSession objects.
+  bool GetAllForeignSessions(std::vector<const ForeignSession*>* sessions);
 
-  // Helper for UpdateFromSyncModel. Appends sync data to a vector of specifics.
-  bool QuerySyncModel(const sync_api::BaseTransaction* trans,
-      std::vector<const sync_pb::SessionSpecifics*>& specifics);
+  // Loads all windows for foreign session with session tag |tag|.
+  // Caller does NOT own ForeignSession objects.
+  bool GetForeignSession(const std::string& tag,
+                         std::vector<SessionWindow*>* windows);
 
-  // Builds sessions from buffered specifics data
-  bool GetSessionData(std::vector<ForeignSession*>* sessions);
+  // Looks up the foreign tab identified by |tab_id| and belonging to foreign
+  // session |tag|.
+  // Caller does NOT own the SessionTab object.
+  bool GetForeignTab(const std::string& tag,
+                     const SessionID::id_type tab_id,
+                     const SessionTab** tab);
 
-  // Helper method to generate session specifics from session windows.
-  void FillSpecificsFromSessions(std::vector<SessionWindow*>* windows,
-      sync_pb::SessionSpecifics* session);
+  // Specifies whether the window has tabs to sync. The new tab page does not
+  // count. If no tabs to sync, it returns true, otherwise false;
+  static bool SessionWindowHasNoTabsToSync(const SessionWindow& window);
 
-  // Helper method for converting session specifics to windows.
-  void AppendForeignSessionFromSpecifics(
-      const sync_pb::SessionSpecifics* specifics,
-      std::vector<ForeignSession*>* session);
+  // Control which local tabs we're interested in syncing.
+  // Ensures the profile matches sync's profile and that the tab has at least
+  // one navigation entry and is not an empty tab.
+  bool IsValidTab(const TabContents& tab);
 
-  // Fills the given empty vector with foreign session windows to restore.
-  // If the vector is returned empty, then the session data could not be
-  // converted back into windows.
-  void AppendForeignSessionWithID(int64 id,
-      std::vector<ForeignSession*>* session,
-      sync_api::BaseTransaction* trans);
+  // Control which foreign tabs we're interested in displaying.
+  // Checks that the tab has navigations and is not a new tab.
+  // Note: a new tab page with back/forward history is valid.
+  static bool IsValidSessionTab(const SessionTab& tab);
 
   // Returns the syncable model type.
   static syncable::ModelType model_type() { return syncable::SESSIONS; }
@@ -147,60 +179,225 @@ class SessionModelAssociator : public PerDataTypeAssociatorInterface<
  private:
   FRIEND_TEST_ALL_PREFIXES(ProfileSyncServiceSessionTest, WriteSessionToNode);
   FRIEND_TEST_ALL_PREFIXES(ProfileSyncServiceSessionTest,
+                           WriteFilledSessionToNode);
+  FRIEND_TEST_ALL_PREFIXES(ProfileSyncServiceSessionTest,
                            WriteForeignSessionToNode);
-
-  // Returns the session service from |sync_service_|.
-  SessionService* GetSessionService();
+  FRIEND_TEST_ALL_PREFIXES(ProfileSyncServiceSessionTest, TabNodePoolEmpty);
+  FRIEND_TEST_ALL_PREFIXES(ProfileSyncServiceSessionTest, TabNodePoolNonEmpty);
+  FRIEND_TEST_ALL_PREFIXES(SessionModelAssociatorTest, PopulateSessionWindow);
+  FRIEND_TEST_ALL_PREFIXES(SessionModelAssociatorTest, PopulateSessionTab);
+
+  // Keep all the links to local tab data in one place.
+  class TabLinks {
+   public:
+    // To support usage as second value in maps we need default and copy
+    // constructors.
+    TabLinks()
+        : sync_id_(0),
+          session_tab_(NULL),
+          tab_(NULL) {}
+
+    // We only ever have either a SessionTab (for foreign tabs), or a
+    // TabContents (for local tabs).
+    TabLinks(int64 sync_id, const TabContents* tab)
+      : sync_id_(sync_id),
+        session_tab_(NULL) {
+      tab_ = const_cast<TabContents*>(tab);
+    }
+    TabLinks(int64 sync_id, const SessionTab* session_tab)
+      : sync_id_(sync_id),
+        tab_(NULL) {
+      session_tab_ = const_cast<SessionTab*>(session_tab);
+    }
+
+    inline int64 sync_id() const { return sync_id_; }
+    inline const SessionTab* session_tab() const { return session_tab_; }
+    inline const TabContents* tab() const { return tab_; }
+   private:
+    int64 sync_id_;
+    SessionTab* session_tab_;
+    TabContents* tab_;
+  };
+
+  // A pool for managing free/used tab sync nodes. Performs lazy creation
+  // of sync nodes when necessary.
+  class TabNodePool {
+   public:
+    explicit TabNodePool(ProfileSyncService* sync_service);
+
+    // Add a previously allocated tab sync node to our pool. Increases the size
+    // of tab_syncid_pool_ by one and marks the new tab node as free.
+    // Note: this should only be called when we discover tab sync nodes from
+    // previous sessions, not for freeing tab nodes we created through
+    // GetFreeTabNode (use FreeTabNode below for that).
+    void AddTabNode(int64 sync_id);
+
+    // Returns the sync_id for the next free tab node. If none are available,
+    // creates a new tab node.
+    // Note: We make use of the following "id's"
+    // - a sync_id: an int64 used in |sync_api::InitByIdLookup|
+    // - a tab_id: created by session service, unique to this client
+    // - a tab_node_id: the id for a particular sync tab node. This is used
+    //   to generate the sync tab node tag through:
+    //       tab_tag = StringPrintf("%s_%ui", local_session_tag, tab_node_id);
+    // tab_node_id and sync_id are both unique to a particular sync node. The
+    // difference is that tab_node_id is controlled by the model associator and
+    // is used when creating a new sync node, which returns the sync_id, created
+    // by the sync db.
+    int64 GetFreeTabNode();
+
+    // Return a tab node to our free pool.
+    // Note: the difference between FreeTabNode and AddTabNode is that
+    // FreeTabNode does not modify the size of |tab_syncid_pool_|, while
+    // AddTabNode increases it by one. In the case of FreeTabNode, the size of
+    // the |tab_syncid_pool_| should always be equal to the amount of tab nodes
+    // associated with this machine.
+    void FreeTabNode(int64 sync_id);
+
+    // Clear tab pool.
+    inline void clear() { tab_syncid_pool_.clear(); }
+
+    // Return the number of tab nodes this client currently has allocated
+    // (including both free and used nodes)
+    inline size_t capacity() const { return tab_syncid_pool_.size(); }
+
+    // Return empty status (all tab nodes are in use).
+    inline bool empty() const { return tab_pool_fp_ == -1; }
+
+    // Return full status (no tab nodes are in use).
+    inline bool full() {
+      return tab_pool_fp_ == static_cast<int64>(tab_syncid_pool_.size())-1;
+    }
+
+    inline void set_machine_tag(const std::string& machine_tag) {
+      machine_tag_ = machine_tag;
+    }
+   private:
+    // Pool of all available syncid's for tab's we have created.
+    std::vector<int64> tab_syncid_pool_;
+
+    // Free pointer for tab pool. Only those node id's, up to and including the
+    // one indexed by the free pointer, are valid and free. The rest of the
+    // |tab_syncid_pool_| is invalid because the nodes are in use.
+    // To get the next free node, use tab_syncid_pool_[tab_pool_fp_--].
+    int64 tab_pool_fp_;
+
+    // The machiine tag associated with this tab pool. Used in the title of new
+    // sync nodes.
+    std::string machine_tag_;
+
+    // Our sync service profile (for making changes to the sync db)
+    ProfileSyncService* sync_service_;
+
+    DISALLOW_COPY_AND_ASSIGN(TabNodePool);
+  };
+
+  // Datatypes for accessing local tab data.
+  typedef std::map<SessionID::id_type, TabLinks> TabLinksMap;
+
+  // Delete all foreign session/window/tab objects allocated dynamically.
+  // This is comprised of ForeignSession*, IDToSessionTabMap*, and any orphaned
+  // SessionTab*'s.
+  void DeleteForeignSessions();
+
+  // Determine if a window is of a type we're interested in syncing.
+  static bool ShouldSyncWindowType(const Browser::Type& type);
+
+  // Build a sync tag from tab_node_id.
+  static inline std::string TabIdToTag(
+      const std::string machine_tag,
+      size_t tab_node_id) {
+    return StringPrintf("%s %lu",
+        machine_tag.c_str(), static_cast<unsigned long>(tab_node_id));
+  }
 
   // Initializes the tag corresponding to this machine.
-  // Note: creates a syncable::BaseTransaction.
-  void InitializeCurrentMachineTag();
+  void InitializeCurrentMachineTag(sync_api::WriteTransaction* trans);
 
-  // Populates the navigation portion of the session specifics.
-  void PopulateSessionSpecificsNavigation(const TabNavigation* navigation,
-      sync_pb::TabNavigation* tab_navigation);
+  // Updates the server data based upon the current client session.  If no node
+  // corresponding to this machine exists in the sync model, one is created.
+  void UpdateSyncModelDataFromClient();
 
-  // Populates the tab portion of the session specifics.
-  void PopulateSessionSpecificsTab(const SessionTab* tab,
-      sync_pb::SessionTab* session_tab);
+  // Pulls the current sync model from the sync database and returns true upon
+  // update of the client model. Will associate any foreign sessions as well as
+  // keep track of any local tab nodes, adding them to our free tab node pool.
+  bool UpdateAssociationsFromSyncModel(const sync_api::ReadNode& root,
+                                       const sync_api::BaseTransaction* trans);
 
-  // Populates the window portion of the session specifics.
-  void PopulateSessionSpecificsWindow(const SessionWindow* window,
-      sync_pb::SessionWindow* session_window);
+  // Fills a tab sync node with data from a TabContents object.
+  // (from a local navigation event)
+  bool WriteTabContentsToSyncModel(const TabContents& tab,
+                                   const int64 sync_id,
+                                   sync_api::WriteTransaction* trans);
+
+  // Used to populate a session window from the session specifics window
+  // provided. Tracks any foreign session data created through |tracker|.
+  static void PopulateSessionWindowFromSpecifics(
+      std::string foreign_session_tag,
+      const sync_pb::SessionWindow& window,
+      const int64 mtime,
+      SessionWindow* session_window,
+      ForeignSessionTracker* tracker);
+
+  // Used to populate a session tab from the session specifics tab provided.
+  static void PopulateSessionTabFromSpecifics(const sync_pb::SessionTab& tab,
+                                              const int64 mtime,
+                                              SessionTab* session_tab);
 
-  // Specifies whether the window has tabs to sync.  The new tab page does not
-  // count.  If no tabs to sync, it returns true, otherwise false;
-  bool WindowHasNoTabsToSync(const SessionWindow* window);
+  // Used to populate a session tab from the session specifics tab provided.
+  static void AppendSessionTabNavigation(
+     const sync_pb::TabNavigation& navigation,
+     std::vector<TabNavigation>* navigations);
+
+  // Populates the navigation portion of the session specifics.
+  static void PopulateSessionSpecificsNavigation(
+     const TabNavigation* navigation,
+     sync_pb::TabNavigation* tab_navigation);
+
+  // Returns the session service from |sync_service_|.
+  SessionService* GetSessionService();
 
   // Internal method used in the callback to obtain the current session.
   // We don't own |windows|.
   void OnGotSession(int handle, std::vector<SessionWindow*>* windows);
 
-  // Used to populate a session tab from the session specifics tab provided.
-  void AppendSessionTabNavigation(std::vector<TabNavigation>* navigations,
-      const sync_pb::TabNavigation* navigation);
+  // Populate a session specifics header from a list of SessionWindows
+  void PopulateSessionSpecificsHeader(
+      const std::vector<SessionWindow*>& windows,
+      sync_pb::SessionHeader* header_s);
 
-  // Used to populate a session tab from the session specifics tab provided.
-  void PopulateSessionTabFromSpecifics(SessionTab* session_tab,
-      const sync_pb::SessionTab* tab, SessionID id);
+  // Populates the window portion of the session specifics.
+  void PopulateSessionSpecificsWindow(const SessionWindow& window,
+                                      sync_pb::SessionWindow* session_window);
 
-  // Used to populate a session window from the session specifics window
-  // provided.
-  void PopulateSessionWindowFromSpecifics(SessionWindow* session_window,
-      const sync_pb::SessionWindow* window);
-
-  // Updates the current session on the server.  Creates a node for this machine
-  // if there is not one already.
-  bool UpdateSyncModel(sync_pb::SessionSpecifics* session_data,
-                    sync_api::WriteTransaction* trans,
-                    const sync_api::ReadNode* root);
-  // Stores the machine tag.
+  // Syncs all the tabs in |window| with the local sync db. Will allocate tab
+  // nodes if needed.
+  bool SyncLocalWindowToSyncModel(const SessionWindow& window);
+
+  // Fills a tab sync node with data from a SessionTab object.
+  // (from ReadCurrentSessions)
+  bool WriteSessionTabToSyncModel(const SessionTab& tab,
+                                  const int64 sync_id,
+                                  sync_api::WriteTransaction* trans);
+
+  // Populates the tab portion of the session specifics.
+  void PopulateSessionSpecificsTab(const SessionTab& tab,
+                                   sync_pb::SessionTab* session_tab);
+
+  // Local client name.
   std::string current_machine_tag_;
 
-  // Stores the current set of foreign session specifics.
-  // Used by ForeignSessionHandler through |GetSessionData|.
-  // Built by |QuerySyncModel| via |UpdateFromSyncModel|.
-  std::vector<const sync_pb::SessionSpecifics*> specifics_;
+  // Pool of all used/available sync nodes associated with tabs.
+  TabNodePool tab_pool_;
+
+  // SyncID for the sync node containing all the window information for this
+  // client.
+  int64 local_session_syncid_;
+
+  // Mapping of current open (local) tabs to their sync identifiers.
+  TabLinksMap tab_map_;
+
+  ForeignSessionTracker foreign_session_tracker_;
 
   // Weak pointer.
   ProfileSyncService* sync_service_;
diff --git a/chrome/browser/sync/glue/session_model_associator_unittest.cc b/chrome/browser/sync/glue/session_model_associator_unittest.cc
new file mode 100644
index 0000000..77f3866
--- /dev/null
+++ b/chrome/browser/sync/glue/session_model_associator_unittest.cc
@@ -0,0 +1,163 @@
+// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include <string>
+#include <vector>
+
+#include "base/scoped_ptr.h"
+#include "base/values.h"
+#include "chrome/browser/sessions/session_types.h"
+#include "chrome/browser/sync/glue/session_model_associator.h"
+#include "chrome/common/page_transition_types.h"
+#include "chrome/common/url_constants.h"
+#include "chrome/test/testing_profile.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+using browser_sync::SessionModelAssociator;
+using browser_sync::ForeignSessionTracker;
+namespace browser_sync {
+
+typedef testing::Test SessionModelAssociatorTest;
+
+TEST_F(SessionModelAssociatorTest, SessionWindowHasNoTabsToSync) {
+  SessionWindow win;
+  ASSERT_TRUE(SessionModelAssociator::SessionWindowHasNoTabsToSync(win));
+  scoped_ptr<SessionTab> tab(new SessionTab());
+  win.tabs.push_back(tab.release());
+  ASSERT_TRUE(SessionModelAssociator::SessionWindowHasNoTabsToSync(win));
+  TabNavigation nav(0, GURL("about:bubba"), GURL("about:referrer"),
+                    string16(ASCIIToUTF16("title")),
+                    std::string("state"), 0U);
+  win.tabs[0]->navigations.push_back(nav);
+  ASSERT_FALSE(SessionModelAssociator::SessionWindowHasNoTabsToSync(win));
+}
+
+TEST_F(SessionModelAssociatorTest, IsValidSessionTab) {
+  SessionTab tab;
+  ASSERT_FALSE(SessionModelAssociator::IsValidSessionTab(tab));
+  TabNavigation nav(0, GURL(chrome::kChromeUINewTabURL),
+                    GURL("about:referrer"),
+                    string16(ASCIIToUTF16("title")),
+                    std::string("state"), 0U);
+  tab.navigations.push_back(nav);
+  // NewTab does not count as valid if it's the only navigation.
+  ASSERT_FALSE(SessionModelAssociator::IsValidSessionTab(tab));
+  TabNavigation nav2(0, GURL("about:bubba"),
+                    GURL("about:referrer"),
+                    string16(ASCIIToUTF16("title")),
+                    std::string("state"), 0U);
+  tab.navigations.push_back(nav2);
+  // Once there's another navigation, the tab is valid.
+  ASSERT_TRUE(SessionModelAssociator::IsValidSessionTab(tab));
+}
+
+TEST_F(SessionModelAssociatorTest, PopulateSessionWindow) {
+  sync_pb::SessionWindow window_s;
+  window_s.add_tab(0);
+  window_s.set_browser_type(sync_pb::SessionWindow_BrowserType_TYPE_NORMAL);
+  window_s.set_selected_tab_index(1);
+
+  std::string tag = "tag";
+  ForeignSessionTracker tracker;
+  ForeignSession* session = tracker.GetForeignSession(tag);
+  SessionWindow* win = new SessionWindow();
+  session->windows.push_back(win);
+  SessionModelAssociator::PopulateSessionWindowFromSpecifics(
+      tag, window_s, 0, win, &tracker);
+  ASSERT_EQ(1U, win->tabs.size());
+  ASSERT_EQ(1, win->selected_tab_index);
+  ASSERT_EQ(1, win->type);
+  ASSERT_EQ(1U, tracker.num_foreign_sessions());
+  ASSERT_EQ(1U, tracker.num_foreign_tabs(std::string("tag")));
+
+  // We do this so that when the destructor for the tracker is called, it will
+  // be able to delete the session, window, and tab. We can't delete these
+  // ourselves, otherwise we would run into double free errors when the
+  // destructor was invoked (the true argument tells the tracker the tab
+  // is now associated with a window).
+  ASSERT_TRUE(tracker.GetSessionTab(tag, 0, true));
+}
+
+TEST_F(SessionModelAssociatorTest, PopulateSessionTab) {
+  sync_pb::SessionTab tab_s;
+  tab_s.set_tab_visual_index(13);
+  tab_s.set_current_navigation_index(3);
+  tab_s.set_pinned(true);
+  tab_s.set_extension_app_id("app_id");
+  sync_pb::TabNavigation* navigation = tab_s.add_navigation();
+  navigation->set_index(12);
+  navigation->set_virtual_url("http://foo/1");
+  navigation->set_referrer("referrer");
+  navigation->set_title("title");
+  navigation->set_page_transition(sync_pb::TabNavigation_PageTransition_TYPED);
+
+  SessionTab tab;
+  SessionModelAssociator::PopulateSessionTabFromSpecifics(tab_s, 0, &tab);
+  ASSERT_EQ(13, tab.tab_visual_index);
+  ASSERT_EQ(3, tab.current_navigation_index);
+  ASSERT_TRUE(tab.pinned);
+  ASSERT_EQ("app_id", tab.extension_app_id);
+  ASSERT_EQ(12, tab.navigations[0].index());
+  ASSERT_EQ(GURL("referrer"), tab.navigations[0].referrer());
+  ASSERT_EQ(string16(ASCIIToUTF16("title")), tab.navigations[0].title());
+  ASSERT_EQ(PageTransition::TYPED, tab.navigations[0].transition());
+  ASSERT_EQ(GURL("http://foo/1"), tab.navigations[0].virtual_url());
+}
+
+TEST_F(SessionModelAssociatorTest, ForeignSessionTracker) {
+  const std::string tag1 = "tag";
+  const std::string tag2 = "tag2";
+  const std::string tag3 = "tag3";
+  ForeignSessionTracker tracker;
+  ASSERT_TRUE(tracker.empty());
+  ASSERT_EQ(0U, tracker.num_foreign_sessions());
+  ASSERT_EQ(0U, tracker.num_foreign_tabs(tag1));
+  SessionTab* tab = tracker.GetSessionTab(tag1, 0, false);
+  ASSERT_EQ(1U, tracker.num_foreign_tabs(tag1));
+  ASSERT_EQ(0U, tracker.num_foreign_sessions());
+  SessionTab* tab2 = tracker.GetSessionTab(tag1, 0, false);
+  ASSERT_EQ(1U, tracker.num_foreign_tabs(tag1));
+  ASSERT_EQ(0U, tracker.num_foreign_sessions());
+  ASSERT_EQ(tab, tab2);
+  tab2 = tracker.GetSessionTab(tag2, 0, false);
+  ASSERT_EQ(1U, tracker.num_foreign_tabs(tag1));
+  ASSERT_EQ(1U, tracker.num_foreign_tabs(tag2));
+  ASSERT_EQ(0U, tracker.num_foreign_sessions());
+
+  ASSERT_FALSE(tracker.DeleteForeignSession(tag1));
+  ASSERT_FALSE(tracker.DeleteForeignSession(tag3));
+
+  ForeignSession* session = tracker.GetForeignSession(tag1);
+  ForeignSession* session2 = tracker.GetForeignSession(tag2);
+  ForeignSession* session3 = tracker.GetForeignSession(tag3);
+  ASSERT_EQ(3U, tracker.num_foreign_sessions());
+
+  ASSERT_TRUE(session);
+  ASSERT_TRUE(session2);
+  ASSERT_TRUE(session3);
+  ASSERT_NE(session, session2);
+  ASSERT_NE(session2, session3);
+  ASSERT_TRUE(tracker.DeleteForeignSession(tag3));
+  ASSERT_EQ(2U, tracker.num_foreign_sessions());
+
+  const SessionTab *tab_ptr;
+  ASSERT_TRUE(tracker.LookupSessionTab(tag1, 0, &tab_ptr));
+  ASSERT_EQ(tab_ptr, tab);
+
+  std::vector<SessionWindow*> windows;
+  ASSERT_TRUE(tracker.LookupSessionWindows(tag1, &windows));
+  ASSERT_EQ(0U, windows.size());
+
+  // The sessions don't have valid windows, lookup should not succeed.
+  std::vector<const ForeignSession*> sessions;
+  ASSERT_FALSE(tracker.LookupAllForeignSessions(&sessions));
+
+  tracker.clear();
+  ASSERT_EQ(0U, tracker.num_foreign_tabs(tag1));
+  ASSERT_EQ(0U, tracker.num_foreign_tabs(tag2));
+  ASSERT_EQ(0U, tracker.num_foreign_sessions());
+}
+
+}  // namespace browser_sync
+
diff --git a/chrome/browser/sync/glue/sync_backend_host.h b/chrome/browser/sync/glue/sync_backend_host.h
index fdfc7b4..3543a4f 100644
--- a/chrome/browser/sync/glue/sync_backend_host.h
+++ b/chrome/browser/sync/glue/sync_backend_host.h
@@ -14,7 +14,7 @@
 #include "base/lock.h"
 #include "base/message_loop.h"
 #include "base/ref_counted.h"
-#include "base/thread.h"
+#include "base/threading/thread.h"
 #include "base/timer.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/browser/sync/engine/syncapi.h"
diff --git a/chrome/browser/sync/glue/sync_backend_host_mock.cc b/chrome/browser/sync/glue/sync_backend_host_mock.cc
new file mode 100644
index 0000000..fe488ad
--- /dev/null
+++ b/chrome/browser/sync/glue/sync_backend_host_mock.cc
@@ -0,0 +1,26 @@
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chrome/browser/sync/glue/sync_backend_host_mock.h"
+
+namespace browser_sync {
+
+SyncBackendHostMock::SyncBackendHostMock() {
+  // By default, the RequestPause and RequestResume methods will
+  // send the confirmation notification and return true.
+  ON_CALL(*this, RequestPause()).
+      WillByDefault(testing::DoAll(Notify(NotificationType::SYNC_PAUSED),
+                                   testing::Return(true)));
+  ON_CALL(*this, RequestResume()).
+      WillByDefault(testing::DoAll(Notify(NotificationType::SYNC_RESUMED),
+                                   testing::Return(true)));
+
+  // By default, invoke the ready callback.
+  ON_CALL(*this, ConfigureDataTypes(testing::_, testing::_)).
+      WillByDefault(InvokeTask());
+}
+
+SyncBackendHostMock::~SyncBackendHostMock() {}
+
+}  // namespace browser_sync
diff --git a/chrome/browser/sync/glue/sync_backend_host_mock.h b/chrome/browser/sync/glue/sync_backend_host_mock.h
index 4035f97..e133a57 100644
--- a/chrome/browser/sync/glue/sync_backend_host_mock.h
+++ b/chrome/browser/sync/glue/sync_backend_host_mock.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
@@ -23,20 +23,8 @@ ACTION(InvokeTask) {
 
 class SyncBackendHostMock : public SyncBackendHost {
  public:
-  SyncBackendHostMock() {
-    // By default, the RequestPause and RequestResume methods will
-    // send the confirmation notification and return true.
-    ON_CALL(*this, RequestPause()).
-        WillByDefault(testing::DoAll(Notify(NotificationType::SYNC_PAUSED),
-                                     testing::Return(true)));
-    ON_CALL(*this, RequestResume()).
-        WillByDefault(testing::DoAll(Notify(NotificationType::SYNC_RESUMED),
-                                     testing::Return(true)));
-
-    // By default, invoke the ready callback.
-    ON_CALL(*this, ConfigureDataTypes(testing::_, testing::_)).
-        WillByDefault(InvokeTask());
-  }
+  SyncBackendHostMock();
+  virtual ~SyncBackendHostMock();
 
   MOCK_METHOD2(ConfigureDataTypes,
                void(const std::set<syncable::ModelType>&, CancelableTask*));
diff --git a/chrome/browser/sync/glue/ui_model_worker.cc b/chrome/browser/sync/glue/ui_model_worker.cc
index 24622ae..38f4a98 100644
--- a/chrome/browser/sync/glue/ui_model_worker.cc
+++ b/chrome/browser/sync/glue/ui_model_worker.cc
@@ -6,7 +6,7 @@
 
 #include "base/message_loop.h"
 #include "base/third_party/dynamic_annotations/dynamic_annotations.h"
-#include "base/waitable_event.h"
+#include "base/synchronization/waitable_event.h"
 
 namespace browser_sync {
 
@@ -32,7 +32,7 @@ void UIModelWorker::DoWorkAndWaitUntilDone(Callback0::Type* work) {
     // We lock only to avoid PostTask'ing a NULL pending_work_ (because it
     // could get Run() in Stop() and call OnTaskCompleted before we post).
     // The task is owned by the message loop as per usual.
-    AutoLock lock(lock_);
+    base::AutoLock lock(lock_);
     DCHECK(!pending_work_);
     pending_work_ = new CallDoWorkAndSignalTask(work, &work_done, this);
     ui_loop_->PostTask(FROM_HERE, pending_work_);
@@ -54,7 +54,7 @@ UIModelWorker::~UIModelWorker() {
 }
 
 void UIModelWorker::OnSyncerShutdownComplete() {
-  AutoLock lock(lock_);
+  base::AutoLock lock(lock_);
   // The SyncerThread has terminated and we are no longer needed by syncapi.
   // The UI loop initiated shutdown and is (or will be) waiting in Stop().
   // We could either be WORKING or RUNNING_MANUAL_SHUTDOWN_PUMP, depending
@@ -69,7 +69,7 @@ void UIModelWorker::OnSyncerShutdownComplete() {
 void UIModelWorker::Stop() {
   DCHECK_EQ(MessageLoop::current(), ui_loop_);
 
-  AutoLock lock(lock_);
+  base::AutoLock lock(lock_);
   DCHECK_EQ(state_, WORKING);
 
   // We're on our own now, the beloved UI MessageLoop is no longer running.
diff --git a/chrome/browser/sync/glue/ui_model_worker.h b/chrome/browser/sync/glue/ui_model_worker.h
index f3a988b..503d8cb 100644
--- a/chrome/browser/sync/glue/ui_model_worker.h
+++ b/chrome/browser/sync/glue/ui_model_worker.h
@@ -7,8 +7,8 @@
 #pragma once
 
 #include "base/callback.h"
-#include "base/condition_variable.h"
-#include "base/lock.h"
+#include "base/synchronization/lock.h"
+#include "base/synchronization/condition_variable.h"
 #include "base/task.h"
 #include "chrome/browser/sync/engine/syncapi.h"
 #include "chrome/browser/sync/engine/model_safe_worker.h"
@@ -119,14 +119,14 @@ class UIModelWorker : public browser_sync::ModelSafeWorker {
   // barrier permits instructions to be reordered by compiler optimizations.
   // Possible or not, that route makes for very fragile code due to existence
   // of theoretical races.
-  Lock lock_;
+  base::Lock lock_;
 
   // Used as a barrier at shutdown to ensure the SyncerThread terminates before
   // we allow the UI thread to return from Stop(). This gets signalled whenever
   // one of two events occur: a new pending_work_ task was scheduled, or the
   // SyncerThread has terminated. We only care about (1) when we are in Stop(),
   // because we have to manually Run() the task.
-  ConditionVariable syncapi_event_;
+  base::ConditionVariable syncapi_event_;
 
   DISALLOW_COPY_AND_ASSIGN(UIModelWorker);
 };
diff --git a/chrome/browser/sync/glue/ui_model_worker_unittest.cc b/chrome/browser/sync/glue/ui_model_worker_unittest.cc
index e71a254..a2a1dde 100644
--- a/chrome/browser/sync/glue/ui_model_worker_unittest.cc
+++ b/chrome/browser/sync/glue/ui_model_worker_unittest.cc
@@ -5,8 +5,8 @@
 #include "base/callback.h"
 #include "base/message_loop.h"
 #include "base/ref_counted.h"
-#include "base/thread.h"
-#include "base/waitable_event.h"
+#include "base/threading/thread.h"
+#include "base/synchronization/waitable_event.h"
 #include "chrome/browser/sync/engine/syncapi.h"
 #include "chrome/browser/sync/glue/ui_model_worker.h"
 #include "testing/gtest/include/gtest/gtest.h"
diff --git a/chrome/browser/sync/notifier/cache_invalidation_packet_handler.h b/chrome/browser/sync/notifier/cache_invalidation_packet_handler.h
index ac2d0c4..a879836 100644
--- a/chrome/browser/sync/notifier/cache_invalidation_packet_handler.h
+++ b/chrome/browser/sync/notifier/cache_invalidation_packet_handler.h
@@ -13,8 +13,8 @@
 
 #include "base/basictypes.h"
 #include "base/gtest_prod_util.h"
-#include "base/non_thread_safe.h"
 #include "base/scoped_callback_factory.h"
+#include "base/threading/non_thread_safe.h"
 #include "base/weak_ptr.h"
 
 namespace invalidation {
@@ -52,7 +52,7 @@ class CacheInvalidationPacketHandler {
 
   void HandleInboundPacket(const std::string& packet);
 
-  NonThreadSafe non_thread_safe_;
+  base::NonThreadSafe non_thread_safe_;
   base::ScopedCallbackFactory<CacheInvalidationPacketHandler>
       scoped_callback_factory_;
 
diff --git a/chrome/browser/sync/notifier/chrome_invalidation_client.h b/chrome/browser/sync/notifier/chrome_invalidation_client.h
index e408085..99af02c 100644
--- a/chrome/browser/sync/notifier/chrome_invalidation_client.h
+++ b/chrome/browser/sync/notifier/chrome_invalidation_client.h
@@ -12,9 +12,9 @@
 #include <string>
 
 #include "base/basictypes.h"
-#include "base/non_thread_safe.h"
 #include "base/scoped_callback_factory.h"
 #include "base/scoped_ptr.h"
+#include "base/threading/non_thread_safe.h"
 #include "base/weak_ptr.h"
 #include "chrome/browser/sync/notifier/chrome_system_resources.h"
 #include "chrome/browser/sync/notifier/state_writer.h"
@@ -99,7 +99,7 @@ class ChromeInvalidationClient
   void HandleOutboundPacket(
       invalidation::NetworkEndpoint* const& network_endpoint);
 
-  NonThreadSafe non_thread_safe_;
+  base::NonThreadSafe non_thread_safe_;
   ChromeSystemResources chrome_system_resources_;
   base::ScopedCallbackFactory<ChromeInvalidationClient>
       scoped_callback_factory_;
diff --git a/chrome/browser/sync/notifier/chrome_system_resources.h b/chrome/browser/sync/notifier/chrome_system_resources.h
index b6e6256..06b8001 100644
--- a/chrome/browser/sync/notifier/chrome_system_resources.h
+++ b/chrome/browser/sync/notifier/chrome_system_resources.h
@@ -14,9 +14,9 @@
 #include <string>
 
 #include "base/message_loop.h"
-#include "base/non_thread_safe.h"
 #include "base/scoped_ptr.h"
 #include "base/task.h"
+#include "base/threading/non_thread_safe.h"
 #include "chrome/browser/sync/notifier/state_writer.h"
 #include "google/cacheinvalidation/invalidation-client.h"
 
@@ -52,7 +52,7 @@ class ChromeSystemResources : public invalidation::SystemResources {
                           invalidation::StorageCallback* callback);
 
  private:
-  NonThreadSafe non_thread_safe_;
+  base::NonThreadSafe non_thread_safe_;
   scoped_ptr<ScopedRunnableMethodFactory<ChromeSystemResources> >
       scoped_runnable_method_factory_;
   // Holds all posted tasks that have not yet been run.
diff --git a/chrome/browser/sync/notifier/registration_manager.h b/chrome/browser/sync/notifier/registration_manager.h
index 1b1a534..2694373 100644
--- a/chrome/browser/sync/notifier/registration_manager.h
+++ b/chrome/browser/sync/notifier/registration_manager.h
@@ -12,7 +12,7 @@
 #include <map>
 
 #include "base/basictypes.h"
-#include "base/non_thread_safe.h"
+#include "base/threading/non_thread_safe.h"
 #include "chrome/browser/sync/syncable/model_type.h"
 #include "google/cacheinvalidation/invalidation-client.h"
 
@@ -54,7 +54,7 @@ class RegistrationManager {
 
   void OnRegister(const invalidation::RegistrationUpdateResult& result);
 
-  NonThreadSafe non_thread_safe_;
+  base::NonThreadSafe non_thread_safe_;
   // Weak pointer.
   invalidation::InvalidationClient* invalidation_client_;
   RegistrationStatusMap registration_status_;
diff --git a/chrome/browser/sync/profile_sync_factory_mock.cc b/chrome/browser/sync/profile_sync_factory_mock.cc
index 68fc045..2d92100 100644
--- a/chrome/browser/sync/profile_sync_factory_mock.cc
+++ b/chrome/browser/sync/profile_sync_factory_mock.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
@@ -11,6 +11,8 @@ using browser_sync::ChangeProcessor;
 using testing::_;
 using testing::InvokeWithoutArgs;
 
+ProfileSyncFactoryMock::ProfileSyncFactoryMock() {}
+
 ProfileSyncFactoryMock::ProfileSyncFactoryMock(
     AssociatorInterface* bookmark_model_associator,
     ChangeProcessor* bookmark_change_processor)
@@ -23,6 +25,8 @@ ProfileSyncFactoryMock::ProfileSyncFactoryMock(
               &ProfileSyncFactoryMock::MakeBookmarkSyncComponents));
 }
 
+ProfileSyncFactoryMock::~ProfileSyncFactoryMock() {}
+
 ProfileSyncFactory::SyncComponents
 ProfileSyncFactoryMock::MakeBookmarkSyncComponents() {
   return SyncComponents(bookmark_model_associator_.release(),
diff --git a/chrome/browser/sync/profile_sync_factory_mock.h b/chrome/browser/sync/profile_sync_factory_mock.h
index f5210a0..a1d1a15 100644
--- a/chrome/browser/sync/profile_sync_factory_mock.h
+++ b/chrome/browser/sync/profile_sync_factory_mock.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
@@ -18,10 +18,11 @@ class ChangeProcessor;
 
 class ProfileSyncFactoryMock : public ProfileSyncFactory {
  public:
-  ProfileSyncFactoryMock() {}
+  ProfileSyncFactoryMock();
   ProfileSyncFactoryMock(
       browser_sync::AssociatorInterface* bookmark_model_associator,
       browser_sync::ChangeProcessor* bookmark_change_processor);
+  virtual ~ProfileSyncFactoryMock();
 
   MOCK_METHOD1(CreateProfileSyncService,
                ProfileSyncService*(const std::string&));
diff --git a/chrome/browser/sync/profile_sync_service.cc b/chrome/browser/sync/profile_sync_service.cc
index a3da689..852ed4b 100644
--- a/chrome/browser/sync/profile_sync_service.cc
+++ b/chrome/browser/sync/profile_sync_service.cc
@@ -19,6 +19,7 @@
 #include "base/string_util.h"
 #include "base/task.h"
 #include "base/utf_string_conversions.h"
+#include "chrome/browser/browser_signin.h"
 #include "chrome/browser/history/history_types.h"
 #include "chrome/browser/platform_util.h"
 #include "chrome/browser/prefs/pref_service.h"
@@ -31,6 +32,7 @@
 #include "chrome/browser/sync/glue/session_data_type_controller.h"
 #include "chrome/browser/sync/profile_sync_factory.h"
 #include "chrome/browser/sync/signin_manager.h"
+#include "chrome/browser/sync/sync_ui_util.h"
 #include "chrome/browser/sync/token_migrator.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/net/gaia/gaia_constants.h"
@@ -39,6 +41,7 @@
 #include "chrome/common/notification_type.h"
 #include "chrome/common/pref_names.h"
 #include "chrome/common/time_format.h"
+#include "grit/chromium_strings.h"
 #include "grit/generated_resources.h"
 #include "jingle/notifier/communicator/const_communicator.h"
 #include "net/base/cookie_monster.h"
@@ -716,11 +719,7 @@ void ProfileSyncService::ShowLoginDialog(gfx::NativeWindow parent_window) {
   }
 
   wizard_.SetParent(parent_window);
-  // This method will also be called if a passphrase is needed.
-  if (observed_passphrase_required_)
-    wizard_.Step(SyncSetupWizard::ENTER_PASSPHRASE);
-  else
-    wizard_.Step(SyncSetupWizard::GAIA_LOGIN);
+  wizard_.Step(SyncSetupWizard::GAIA_LOGIN);
 
   FOR_EACH_OBSERVER(Observer, observers_, OnStateChanged());
 }
@@ -734,6 +733,31 @@ void ProfileSyncService::ShowConfigure(gfx::NativeWindow parent_window) {
   wizard_.Step(SyncSetupWizard::CONFIGURE);
 }
 
+void ProfileSyncService::PromptForExistingPassphrase(
+    gfx::NativeWindow parent_window) {
+  if (WizardIsVisible()) {
+    wizard_.Focus();
+    return;
+  }
+  wizard_.SetParent(parent_window);
+  wizard_.Step(SyncSetupWizard::ENTER_PASSPHRASE);
+}
+
+void ProfileSyncService::ShowPassphraseMigration(
+    gfx::NativeWindow parent_window) {
+  wizard_.SetParent(parent_window);
+  wizard_.Step(SyncSetupWizard::PASSPHRASE_MIGRATION);
+}
+
+void ProfileSyncService::SigninForPassphrase(TabContents* container) {
+  string16 prefilled_username = GetAuthenticatedUsername();
+  string16 login_message = sync_ui_util::GetLoginMessageForEncryption();
+  profile_->GetBrowserSignin()->RequestSignin(container,
+                                              prefilled_username,
+                                              login_message,
+                                              this);
+}
+
 SyncBackendHost::StatusSummary ProfileSyncService::QuerySyncStatusSummary() {
   if (backend_.get() && backend_initialized_)
     return backend_->GetStatusSummary();
@@ -1138,6 +1162,27 @@ void ProfileSyncService::Observe(NotificationType type,
   }
 }
 
+// This is the delegate callback from BrowserSigin.
+void ProfileSyncService::OnLoginSuccess() {
+  // The reason for the browser signin was a non-explicit passphrase
+  // required signal.  If this is the first time through the passphrase
+  // process, we want to show the migration UI and offer an explicit
+  // passphrase.  Otherwise, we're done because the implicit is enough.
+
+  if (passphrase_required_for_decryption_) {
+    // NOT first time (decrypting something encrypted elsewhere).
+    // Do nothing.
+  } else {
+    ShowPassphraseMigration(NULL);
+  }
+}
+
+// This is the delegate callback from BrowserSigin.
+void ProfileSyncService::OnLoginFailure(const GoogleServiceAuthError& error) {
+  // Do nothing.  The UI will already reflect the fact that the
+  // user is not signed in.
+}
+
 void ProfileSyncService::AddObserver(Observer* observer) {
   observers_.AddObserver(observer);
 }
diff --git a/chrome/browser/sync/profile_sync_service.h b/chrome/browser/sync/profile_sync_service.h
index 19583b6..62a8e07 100644
--- a/chrome/browser/sync/profile_sync_service.h
+++ b/chrome/browser/sync/profile_sync_service.h
@@ -15,6 +15,7 @@
 #include "base/string16.h"
 #include "base/time.h"
 #include "base/timer.h"
+#include "chrome/browser/browser_signin.h"
 #include "chrome/browser/prefs/pref_member.h"
 #include "chrome/browser/sync/engine/syncapi.h"
 #include "chrome/browser/sync/glue/data_type_controller.h"
@@ -37,6 +38,7 @@ class NotificationSource;
 class NotificationType;
 class Profile;
 class ProfileSyncFactory;
+class TabContents;
 class TokenMigrator;
 
 // ProfileSyncService is the layer between browser subsystems like bookmarks,
@@ -83,6 +85,7 @@ class TokenMigrator;
 //
 class ProfileSyncService : public browser_sync::SyncFrontend,
                            public browser_sync::UnrecoverableErrorHandler,
+                           public BrowserSignin::SigninDelegate,
                            public NotificationObserver {
  public:
   typedef ProfileSyncServiceObserver Observer;
@@ -223,6 +226,9 @@ class ProfileSyncService : public browser_sync::SyncFrontend,
   }
   virtual void ShowLoginDialog(gfx::NativeWindow parent_window);
   void ShowConfigure(gfx::NativeWindow parent_window);
+  void PromptForExistingPassphrase(gfx::NativeWindow parent_window);
+  void SigninForPassphrase(TabContents* container);
+  void ShowPassphraseMigration(gfx::NativeWindow parent_window);
 
   // Pretty-printed strings for a given StatusSummary.
   static std::string BuildSyncStatusSummaryText(
@@ -230,6 +236,10 @@ class ProfileSyncService : public browser_sync::SyncFrontend,
 
   // Returns true if the SyncBackendHost has told us it's ready to accept
   // changes.
+  // [REMARK] - it is safe to call this function only from the ui thread.
+  // because the variable is not thread safe and should only be accessed from
+  // single thread. If we want multiple threads to access this(and there is
+  // currently no need to do so) we need to protect this with a lock.
   // TODO(timsteele): What happens if the bookmark model is loaded, a change
   // takes place, and the backend isn't initialized yet?
   bool sync_initialized() const { return backend_initialized_; }
@@ -315,6 +325,10 @@ class ProfileSyncService : public browser_sync::SyncFrontend,
                        const NotificationSource& source,
                        const NotificationDetails& details);
 
+  // BrowserSignin::SigninDelegate interface.
+  virtual void OnLoginSuccess();
+  virtual void OnLoginFailure(const GoogleServiceAuthError& error);
+
   // Changes which data types we're going to be syncing to |preferred_types|.
   // If it is running, the DataTypeManager will be instructed to reconfigure
   // the sync backend so that exactly these datatypes are actively synced.  See
diff --git a/chrome/browser/sync/profile_sync_service_autofill_unittest.cc b/chrome/browser/sync/profile_sync_service_autofill_unittest.cc
index a7b929a..025c573 100644
--- a/chrome/browser/sync/profile_sync_service_autofill_unittest.cc
+++ b/chrome/browser/sync/profile_sync_service_autofill_unittest.cc
@@ -16,7 +16,7 @@
 #include "base/task.h"
 #include "base/time.h"
 #include "base/utf_string_conversions.h"
-#include "base/waitable_event.h"
+#include "base/synchronization/waitable_event.h"
 #include "chrome/browser/autofill/autofill_common_test.h"
 #include "chrome/browser/browser_thread.h"
 #include "chrome/browser/sync/abstract_profile_sync_service_test.h"
@@ -28,10 +28,15 @@
 #include "chrome/browser/sync/glue/autofill_data_type_controller.h"
 #include "chrome/browser/sync/glue/autofill_model_associator.h"
 #include "chrome/browser/sync/glue/autofill_model_associator2.h"
+#include "chrome/browser/sync/glue/autofill_profile_change_processor.h"
+#include "chrome/browser/sync/glue/autofill_profile_data_type_controller.h"
+#include "chrome/browser/sync/glue/autofill_profile_model_associator.h"
+#include "chrome/browser/sync/glue/data_type_controller.h"
 #include "chrome/browser/sync/profile_sync_factory.h"
 #include "chrome/browser/sync/profile_sync_service.h"
 #include "chrome/browser/sync/profile_sync_test_util.h"
 #include "chrome/browser/sync/protocol/autofill_specifics.pb.h"
+#include "chrome/browser/sync/syncable/autofill_migration.h"
 #include "chrome/browser/sync/syncable/syncable.h"
 #include "chrome/browser/sync/syncable/model_type.h"
 #include "chrome/browser/sync/test_profile_sync_service.h"
@@ -47,9 +52,15 @@
 
 using base::Time;
 using base::WaitableEvent;
+using browser_sync::AutofillChangeProcessor;
 using browser_sync::AutofillChangeProcessor2;
 using browser_sync::AutofillDataTypeController;
+using browser_sync::AutofillModelAssociator;
 using browser_sync::AutofillModelAssociator2;
+using browser_sync::AutofillProfileChangeProcessor;
+using browser_sync::AutofillProfileDataTypeController;
+using browser_sync::AutofillProfileModelAssociator;
+using browser_sync::DataTypeController;
 using browser_sync::GROUP_DB;
 using browser_sync::kAutofillTag;
 using browser_sync::SyncBackendHostForProfileSyncTest;
@@ -99,9 +110,26 @@ class WebDatabaseMock : public WebDatabase {
   MOCK_METHOD1(AddAutoFillProfile,
                bool(const AutoFillProfile&));  // NOLINT
   MOCK_METHOD1(RemoveAutoFillProfile,
-               bool(int));  // NOLINT
+               bool(const string&));  // NOLINT
 };
 
+class ProfileSyncServiceAutofillTest;
+
+template<class AutoFillProfile>
+syncable::ModelType GetModelType() {
+  return syncable::UNSPECIFIED;
+}
+
+template<>
+syncable::ModelType GetModelType<AutofillEntry>() {
+  return syncable::AUTOFILL;
+}
+
+template<>
+syncable::ModelType GetModelType<AutoFillProfile>() {
+  return syncable::AUTOFILL_PROFILE;
+}
+
 class WebDataServiceFake : public WebDataService {
  public:
   explicit WebDataServiceFake(WebDatabase* web_database)
@@ -118,31 +146,113 @@ class WebDataServiceFake : public WebDataService {
   WebDatabase* web_database_;
 };
 
-class PersonalDataManagerMock: public PersonalDataManager {
- public:
-  MOCK_CONST_METHOD0(IsDataLoaded, bool());
-  MOCK_METHOD0(LoadProfiles, void());
-  MOCK_METHOD0(LoadCreditCards, void());
-  MOCK_METHOD0(Refresh, void());
-};
-
 ACTION_P4(MakeAutofillSyncComponents, service, wd, pdm, dtc) {
   EXPECT_TRUE(BrowserThread::CurrentlyOn(BrowserThread::DB));
   if (!BrowserThread::CurrentlyOn(BrowserThread::DB))
     return ProfileSyncFactory::SyncComponents(NULL, NULL);
-  AutofillModelAssociator2* model_associator =
-      new AutofillModelAssociator2(service, wd, pdm);
-  AutofillChangeProcessor2* change_processor =
-      new AutofillChangeProcessor2(model_associator, wd, pdm, dtc);
+  AutofillModelAssociator* model_associator =
+      new AutofillModelAssociator(service, wd, pdm);
+  AutofillChangeProcessor* change_processor =
+      new AutofillChangeProcessor(model_associator, wd, pdm, dtc);
   return ProfileSyncFactory::SyncComponents(model_associator,
                                             change_processor);
 }
 
+ACTION_P4(MakeAutofillProfileSyncComponents, service, wd, pdm, dtc) {
+  EXPECT_TRUE(BrowserThread::CurrentlyOn(BrowserThread::DB));
+  if (!BrowserThread::CurrentlyOn(BrowserThread::DB))
+    return ProfileSyncFactory::SyncComponents(NULL, NULL);
+  AutofillProfileModelAssociator* model_associator =
+      new AutofillProfileModelAssociator(service, wd, pdm);
+  AutofillProfileChangeProcessor* change_processor =
+      new AutofillProfileChangeProcessor(model_associator, wd, pdm, dtc);
+  return ProfileSyncFactory::SyncComponents(model_associator,
+                                            change_processor);
+}
+
+class AbstractAutofillFactory {
+ public:
+  virtual AutofillDataTypeController* CreateDataTypeController(
+    ProfileSyncFactory *factory,
+      ProfileMock* profile,
+      ProfileSyncService* service) = 0;
+  virtual void SetExpectation(ProfileSyncFactoryMock* factory,
+      ProfileSyncService* service,
+      WebDatabase* wd,
+      PersonalDataManager* pdm,
+      DataTypeController* dtc) = 0;
+  virtual ~AbstractAutofillFactory() {}
+};
+
+class AutofillEntryFactory : public AbstractAutofillFactory {
+ public:
+  browser_sync::AutofillDataTypeController* CreateDataTypeController(
+      ProfileSyncFactory *factory,
+      ProfileMock* profile,
+      ProfileSyncService* service) {
+    return new AutofillDataTypeController(factory,
+        profile,
+        service);
+  }
+
+  void SetExpectation(ProfileSyncFactoryMock* factory,
+      ProfileSyncService* service,
+      WebDatabase* wd,
+      PersonalDataManager* pdm,
+      DataTypeController* dtc) {
+    EXPECT_CALL(*factory, CreateAutofillSyncComponents(_,_,_,_)).
+        WillOnce(MakeAutofillSyncComponents(service, wd, pdm, dtc));
+  }
+};
+
+class AutofillProfileFactory : public AbstractAutofillFactory {
+ public:
+  browser_sync::AutofillDataTypeController* CreateDataTypeController(
+      ProfileSyncFactory *factory,
+      ProfileMock* profile,
+      ProfileSyncService* service) {
+    return new AutofillProfileDataTypeController(factory,
+        profile,
+        service);
+   }
+
+  void SetExpectation(ProfileSyncFactoryMock* factory,
+      ProfileSyncService* service,
+      WebDatabase* wd,
+      PersonalDataManager* pdm,
+      DataTypeController* dtc) {
+    EXPECT_CALL(*factory, CreateAutofillProfileSyncComponents(_,_,_,_)).
+        WillOnce(MakeAutofillProfileSyncComponents(service, wd, pdm, dtc));
+  }
+};
+
+class PersonalDataManagerMock: public PersonalDataManager {
+ public:
+  MOCK_CONST_METHOD0(IsDataLoaded, bool());
+  MOCK_METHOD0(LoadProfiles, void());
+  MOCK_METHOD0(LoadCreditCards, void());
+  MOCK_METHOD0(Refresh, void());
+};
+template <class T> class AddAutofillTask;
+
 class ProfileSyncServiceAutofillTest : public AbstractProfileSyncServiceTest {
  protected:
   ProfileSyncServiceAutofillTest() : db_thread_(BrowserThread::DB) {
   }
 
+  AutofillProfileFactory profile_factory_;
+  AutofillEntryFactory entry_factory_;
+
+  AbstractAutofillFactory* GetFactory(syncable::ModelType type) {
+    if (type == syncable::AUTOFILL) {
+      return &entry_factory_;
+    } else if (type == syncable::AUTOFILL_PROFILE) {
+      return &profile_factory_;
+    } else {
+      NOTREACHED();
+      return NULL;
+    }
+  }
   virtual void SetUp() {
     web_data_service_ = new WebDataServiceFake(&web_database_);
     personal_data_manager_ = new PersonalDataManagerMock();
@@ -162,48 +272,49 @@ class ProfileSyncServiceAutofillTest : public AbstractProfileSyncServiceTest {
     MessageLoop::current()->RunAllPending();
   }
 
-  void StartSyncService(Task* task, bool will_fail_association) {
-    if (!service_.get()) {
-      service_.reset(
-          new TestProfileSyncService(&factory_, &profile_, "test_user", false,
-                                     task));
-      AutofillDataTypeController* data_type_controller =
-          new AutofillDataTypeController(&factory_,
-                                         &profile_,
-                                         service_.get());
-
-     SyncBackendHostForProfileSyncTest::
-         SetDefaultExpectationsForWorkerCreation(&profile_);
-
-      EXPECT_CALL(factory_, CreateAutofillSyncComponents(_, _, _, _)).
-          WillOnce(MakeAutofillSyncComponents(service_.get(),
-                                              &web_database_,
-                                              personal_data_manager_.get(),
-                                              data_type_controller));
-      EXPECT_CALL(factory_, CreateDataTypeManager(_, _)).
-          WillOnce(ReturnNewDataTypeManager());
-
-      EXPECT_CALL(profile_, GetWebDataService(_)).
-          WillOnce(Return(web_data_service_.get()));
-
-      EXPECT_CALL(profile_, GetPersonalDataManager()).
-          WillRepeatedly(Return(personal_data_manager_.get()));
-
-      EXPECT_CALL(*personal_data_manager_, IsDataLoaded()).
-          WillRepeatedly(Return(true));
-
-       // We need tokens to get the tests going
-      token_service_.IssueAuthTokenForTest(
-          GaiaConstants::kSyncService, "token");
-
-      EXPECT_CALL(profile_, GetTokenService()).
-          WillRepeatedly(Return(&token_service_));
-
-      service_->set_num_expected_resumes(will_fail_association ? 0 : 1);
-      service_->RegisterDataTypeController(data_type_controller);
-      service_->Initialize();
-      MessageLoop::current()->Run();
-    }
+  void StartSyncService(Task* task,
+                        bool will_fail_association,
+                        syncable::ModelType type) {
+    AbstractAutofillFactory* factory = GetFactory(type);
+    service_.reset(
+        new TestProfileSyncService(&factory_, &profile_, "test_user", false,
+                                   task));
+    AutofillDataTypeController* data_type_controller =
+        factory->CreateDataTypeController(&factory_,
+            &profile_,
+            service_.get());
+   SyncBackendHostForProfileSyncTest::
+       SetDefaultExpectationsForWorkerCreation(&profile_);
+
+   factory->SetExpectation(&factory_,
+       service_.get(),
+       &web_database_,
+       personal_data_manager_.get(),
+       data_type_controller);
+
+    EXPECT_CALL(factory_, CreateDataTypeManager(_, _)).
+        WillOnce(ReturnNewDataTypeManager());
+
+    EXPECT_CALL(profile_, GetWebDataService(_)).
+        WillOnce(Return(web_data_service_.get()));
+
+    EXPECT_CALL(profile_, GetPersonalDataManager()).
+        WillRepeatedly(Return(personal_data_manager_.get()));
+
+    EXPECT_CALL(*personal_data_manager_, IsDataLoaded()).
+        WillRepeatedly(Return(true));
+
+     // We need tokens to get the tests going
+    token_service_.IssueAuthTokenForTest(
+        GaiaConstants::kSyncService, "token");
+
+    EXPECT_CALL(profile_, GetTokenService()).
+        WillRepeatedly(Return(&token_service_));
+
+    service_->set_num_expected_resumes(will_fail_association ? 0 : 1);
+    service_->RegisterDataTypeController(data_type_controller);
+    service_->Initialize();
+    MessageLoop::current()->Run();
   }
 
   bool AddAutofillSyncNode(const AutofillEntry& entry) {
@@ -214,30 +325,27 @@ class ProfileSyncServiceAutofillTest : public AbstractProfileSyncServiceTest {
       return false;
 
     sync_api::WriteNode node(&trans);
-    std::string tag = AutofillModelAssociator2::KeyToTag(entry.key().name(),
+    std::string tag = AutofillModelAssociator::KeyToTag(entry.key().name(),
                                                         entry.key().value());
     if (!node.InitUniqueByCreation(syncable::AUTOFILL, autofill_root, tag))
       return false;
 
-    AutofillChangeProcessor2::WriteAutofillEntry(entry, &node);
+    AutofillChangeProcessor::WriteAutofillEntry(entry, &node);
     return true;
   }
 
-  bool AddAutofillProfileSyncNode(const AutoFillProfile& profile) {
+  bool AddAutofillSyncNode(const AutoFillProfile& profile) {
     sync_api::WriteTransaction trans(
         service_->backend()->GetUserShareHandle());
     sync_api::ReadNode autofill_root(&trans);
-    if (!autofill_root.InitByTagLookup(browser_sync::kAutofillTag))
+    if (!autofill_root.InitByTagLookup(browser_sync::kAutofillProfileTag))
       return false;
     sync_api::WriteNode node(&trans);
-    std::string tag = browser_sync::AutofillModelAssociator2::ProfileLabelToTag(
-        profile.Label());
-    if (!node.InitUniqueByCreation(syncable::AUTOFILL, autofill_root, tag))
+    std::string tag = profile.guid();
+    if (!node.InitUniqueByCreation(syncable::AUTOFILL_PROFILE,
+        autofill_root, tag))
       return false;
-    AutofillChangeProcessor2::WriteAutofillProfile(profile, &node);
-    sync_pb::AutofillSpecifics s(node.GetAutofillSpecifics());
-    s.mutable_profile()->set_label(UTF16ToUTF8(profile.Label()));
-    node.SetAutofillSpecifics(s);
+    AutofillProfileChangeProcessor::WriteAutofillProfile(profile, &node);
     return true;
   }
 
@@ -268,8 +376,8 @@ class ProfileSyncServiceAutofillTest : public AbstractProfileSyncServiceTest {
         entries->push_back(AutofillEntry(key, timestamps));
       } else if (autofill.has_profile()) {
         AutoFillProfile p;
-        p.set_label(UTF8ToUTF16(autofill.profile().label()));
-        AutofillModelAssociator2::OverwriteProfileWithServerData(&p,
+        p.set_guid(autofill.profile().guid());
+        AutofillProfileModelAssociator::OverwriteProfileWithServerData(&p,
             autofill.profile());
         profiles->push_back(p);
       }
@@ -278,6 +386,31 @@ class ProfileSyncServiceAutofillTest : public AbstractProfileSyncServiceTest {
     return true;
   }
 
+  bool GetAutofillProfilesFromSyncDBUnderProfileNode(
+      std::vector<AutoFillProfile>* profiles) {
+    sync_api::ReadTransaction trans(service_->backend()->GetUserShareHandle());
+    sync_api::ReadNode autofill_root(&trans);
+    if (!autofill_root.InitByTagLookup(browser_sync::kAutofillProfileTag))
+      return false;
+
+    int64 child_id = autofill_root.GetFirstChildId();
+    while (child_id != sync_api::kInvalidId) {
+      sync_api::ReadNode child_node(&trans);
+      if (!child_node.InitByIdLookup(child_id))
+        return false;
+
+      const sync_pb::AutofillProfileSpecifics& autofill(
+          child_node.GetAutofillProfileSpecifics());
+        AutoFillProfile p;
+        p.set_guid(autofill.guid());
+        AutofillProfileModelAssociator::OverwriteProfileWithServerData(&p,
+            autofill);
+        profiles->push_back(p);
+      child_id = child_node.GetSuccessorId();
+    }
+    return true;
+  }
+
   void SetIdleChangeProcessorExpectations() {
     EXPECT_CALL(web_database_, RemoveFormElement(_, _)).Times(0);
     EXPECT_CALL(web_database_, GetAutofillTimestamps(_, _, _)).Times(0);
@@ -303,7 +436,8 @@ class ProfileSyncServiceAutofillTest : public AbstractProfileSyncServiceTest {
     return MakeAutofillEntry(name, value, timestamp, -1);
   }
 
-  friend class AddAutofillEntriesTask;
+  friend class AddAutofillTask<AutofillEntry>;
+  friend class AddAutofillTask<AutoFillProfile>;
   friend class FakeServerUpdater;
 
   BrowserThread db_thread_;
@@ -315,34 +449,28 @@ class ProfileSyncServiceAutofillTest : public AbstractProfileSyncServiceTest {
   scoped_refptr<PersonalDataManagerMock> personal_data_manager_;
 };
 
-class AddAutofillEntriesTask : public Task {
+template <class T>
+class AddAutofillTask : public Task {
  public:
-  AddAutofillEntriesTask(ProfileSyncServiceAutofillTest* test,
-                         const std::vector<AutofillEntry>& entries,
-                         const std::vector<AutoFillProfile>& profiles)
-      : test_(test), entries_(entries), profiles_(profiles), success_(false) {
+  AddAutofillTask(ProfileSyncServiceAutofillTest* test,
+                         const std::vector<T>& entries)
+      : test_(test), entries_(entries), success_(false) {
   }
 
   virtual void Run() {
-    if (!test_->CreateRoot(syncable::AUTOFILL))
+    if (!test_->CreateRoot(GetModelType<T>()))
       return;
     for (size_t i = 0; i < entries_.size(); ++i) {
       if (!test_->AddAutofillSyncNode(entries_[i]))
         return;
     }
-    for (size_t i = 0; i < profiles_.size(); ++i) {
-      if (!test_->AddAutofillProfileSyncNode(profiles_[i]))
-        return;
-    }
     success_ = true;
   }
-
   bool success() { return success_; }
 
  private:
   ProfileSyncServiceAutofillTest* test_;
-  const std::vector<AutofillEntry>& entries_;
-  const std::vector<AutoFillProfile>& profiles_;
+  const std::vector<T>& entries_;
   bool success_;
 };
 
@@ -392,7 +520,7 @@ class FakeServerUpdater: public base::RefCountedThreadSafe<FakeServerUpdater> {
     ASSERT_TRUE(dir.good());
 
     // Create autofill protobuf
-    std::string tag = AutofillModelAssociator2::KeyToTag(entry_.key().name(),
+    std::string tag = AutofillModelAssociator::KeyToTag(entry_.key().name(),
                                                         entry_.key().value());
     sync_pb::AutofillSpecifics new_autofill;
     new_autofill.set_name(UTF16ToUTF8(entry_.key().name()));
@@ -485,7 +613,7 @@ class FakeServerUpdater: public base::RefCountedThreadSafe<FakeServerUpdater> {
 //            waiting for the PersonalDataManager.
 TEST_F(ProfileSyncServiceAutofillTest, FailModelAssociation) {
   // Don't create the root autofill node so startup fails.
-  StartSyncService(NULL, true);
+  StartSyncService(NULL, true, syncable::AUTOFILL);
   EXPECT_TRUE(service_->unrecoverable_error_detected());
 }
 
@@ -495,7 +623,7 @@ TEST_F(ProfileSyncServiceAutofillTest, EmptyNativeEmptySync) {
   SetIdleChangeProcessorExpectations();
   CreateRootTask task(this, syncable::AUTOFILL);
   EXPECT_CALL(*personal_data_manager_, Refresh());
-  StartSyncService(&task, false);
+  StartSyncService(&task, false, syncable::AUTOFILL);
   ASSERT_TRUE(task.success());
   std::vector<AutofillEntry> sync_entries;
   std::vector<AutoFillProfile> sync_profiles;
@@ -513,7 +641,7 @@ TEST_F(ProfileSyncServiceAutofillTest, HasNativeEntriesEmptySync) {
   SetIdleChangeProcessorExpectations();
   CreateRootTask task(this, syncable::AUTOFILL);
   EXPECT_CALL(*personal_data_manager_, Refresh());
-  StartSyncService(&task, false);
+  StartSyncService(&task, false, syncable::AUTOFILL);
   ASSERT_TRUE(task.success());
   std::vector<AutofillEntry> sync_entries;
   std::vector<AutoFillProfile> sync_profiles;
@@ -523,18 +651,15 @@ TEST_F(ProfileSyncServiceAutofillTest, HasNativeEntriesEmptySync) {
   EXPECT_EQ(0U, sync_profiles.size());
 }
 
-TEST_F(ProfileSyncServiceAutofillTest, HasMixedNativeEmptySync) {
-  std::vector<AutofillEntry> entries;
-  entries.push_back(MakeAutofillEntry("foo", "bar", 1));
-  EXPECT_CALL(web_database_, GetAllAutofillEntries(_)).
-      WillOnce(DoAll(SetArgumentPointee<0>(entries), Return(true)));
+TEST_F(ProfileSyncServiceAutofillTest, HasProfileEmptySync) {
 
   std::vector<AutoFillProfile*> profiles;
   std::vector<AutoFillProfile> expected_profiles;
   // Owned by GetAutoFillProfiles caller.
   AutoFillProfile* profile0 = new AutoFillProfile;
-  autofill_test::SetProfileInfo(profile0,
-      "Billing", "Marion", "Mitchell", "Morrison",
+  autofill_test::SetProfileInfoWithGuid(profile0,
+      "{54B3F9AA-335E-4f71-A27D-719C41564230}", "Billing",
+      "Mitchell", "Morrison",
       "johnwayne@me.xyz", "Fox", "123 Zoo St.", "unit 5", "Hollywood", "CA",
       "91601", "US", "12345678910", "01987654321");
   profiles.push_back(profile0);
@@ -543,88 +668,15 @@ TEST_F(ProfileSyncServiceAutofillTest, HasMixedNativeEmptySync) {
       WillOnce(DoAll(SetArgumentPointee<0>(profiles), Return(true)));
   EXPECT_CALL(*personal_data_manager_, Refresh());
   SetIdleChangeProcessorExpectations();
-  CreateRootTask task(this, syncable::AUTOFILL);
-  StartSyncService(&task, false);
+  CreateRootTask task(this, syncable::AUTOFILL_PROFILE);
+  StartSyncService(&task, false, syncable::AUTOFILL_PROFILE);
   ASSERT_TRUE(task.success());
-  std::vector<AutofillEntry> sync_entries;
   std::vector<AutoFillProfile> sync_profiles;
-  ASSERT_TRUE(GetAutofillEntriesFromSyncDB(&sync_entries, &sync_profiles));
-  ASSERT_EQ(1U, entries.size());
-  EXPECT_TRUE(entries[0] == sync_entries[0]);
+  ASSERT_TRUE(GetAutofillProfilesFromSyncDBUnderProfileNode(&sync_profiles));
   EXPECT_EQ(1U, sync_profiles.size());
   EXPECT_EQ(0, expected_profiles[0].Compare(sync_profiles[0]));
 }
 
-bool ProfilesMatchExceptLabelImpl(AutoFillProfile p1, AutoFillProfile p2) {
-  const AutoFillFieldType types[] = { NAME_FIRST,
-                                      NAME_MIDDLE,
-                                      NAME_LAST,
-                                      EMAIL_ADDRESS,
-                                      COMPANY_NAME,
-                                      ADDRESS_HOME_LINE1,
-                                      ADDRESS_HOME_LINE2,
-                                      ADDRESS_HOME_CITY,
-                                      ADDRESS_HOME_STATE,
-                                      ADDRESS_HOME_ZIP,
-                                      ADDRESS_HOME_COUNTRY,
-                                      PHONE_HOME_NUMBER,
-                                      PHONE_FAX_NUMBER };
-  if (p1.Label() == p2.Label())
-    return false;
-
-  for (size_t index = 0; index < arraysize(types); ++index) {
-    if (p1.GetFieldText(AutoFillType(types[index])) !=
-        p2.GetFieldText(AutoFillType(types[index])))
-      return false;
-  }
-  return true;
-}
-
-MATCHER_P(ProfileMatchesExceptLabel, profile, "") {
-  return ProfilesMatchExceptLabelImpl(arg, profile);
-}
-
-TEST_F(ProfileSyncServiceAutofillTest, HasDuplicateProfileLabelsEmptySync) {
-  std::vector<AutoFillProfile> expected_profiles;
-  std::vector<AutoFillProfile*> profiles;
-  AutoFillProfile* profile0 = new AutoFillProfile;
-  autofill_test::SetProfileInfo(profile0,
-      "Billing", "Marion", "Mitchell", "Morrison",
-      "johnwayne@me.xyz", "Fox", "123 Zoo St.", "unit 5", "Hollywood", "CA",
-      "91601", "US", "12345678910", "01987654321");
-  AutoFillProfile* profile1 = new AutoFillProfile;
-  autofill_test::SetProfileInfo(profile1,
-      "Billing", "Same", "Label", "Morrison",
-      "johnwayne@me.xyz", "Fox", "123 Zoo St.", "unit 5", "Hollywood", "CA",
-      "91601", "US", "12345678910", "01987654321");
-  profiles.push_back(profile0);
-  profiles.push_back(profile1);
-  expected_profiles.push_back(*profile0);
-  expected_profiles.push_back(*profile1);
-  AutoFillProfile relabelled_profile;
-  EXPECT_CALL(web_database_, GetAllAutofillEntries(_)).WillOnce(Return(true));
-  EXPECT_CALL(*personal_data_manager_, Refresh());
-  EXPECT_CALL(web_database_, GetAutoFillProfiles(_)).
-      WillOnce(DoAll(SetArgumentPointee<0>(profiles), Return(true)));
-  EXPECT_CALL(web_database_, UpdateAutoFillProfile(
-      ProfileMatchesExceptLabel(expected_profiles[1]))).
-      WillOnce(DoAll(SaveArg<0>(&relabelled_profile), Return(true)));
-
-  SetIdleChangeProcessorExpectations();
-  CreateRootTask task(this, syncable::AUTOFILL);
-  StartSyncService(&task, false);
-  ASSERT_TRUE(task.success());
-  std::vector<AutofillEntry> sync_entries;
-  std::vector<AutoFillProfile> sync_profiles;
-  ASSERT_TRUE(GetAutofillEntriesFromSyncDB(&sync_entries, &sync_profiles));
-  EXPECT_EQ(0U, sync_entries.size());
-  EXPECT_EQ(2U, sync_profiles.size());
-  EXPECT_EQ(0, expected_profiles[0].Compare(sync_profiles[1]));
-  EXPECT_TRUE(ProfilesMatchExceptLabelImpl(expected_profiles[1],
-                                           sync_profiles[0]));
-  EXPECT_EQ(sync_profiles[0].Label(), relabelled_profile.Label());
-}
-
 TEST_F(ProfileSyncServiceAutofillTest, HasNativeWithDuplicatesEmptySync) {
   // There is buggy autofill code that allows duplicate name/value
   // pairs to exist in the database with separate pair_ids.
@@ -638,7 +690,7 @@ TEST_F(ProfileSyncServiceAutofillTest, HasNativeWithDuplicatesEmptySync) {
   SetIdleChangeProcessorExpectations();
   CreateRootTask task(this, syncable::AUTOFILL);
   EXPECT_CALL(*personal_data_manager_, Refresh());
-  StartSyncService(&task, false);
+  StartSyncService(&task, false, syncable::AUTOFILL);
   ASSERT_TRUE(task.success());
   std::vector<AutofillEntry> sync_entries;
   std::vector<AutoFillProfile> sync_profiles;
@@ -649,46 +701,25 @@ TEST_F(ProfileSyncServiceAutofillTest, HasNativeWithDuplicatesEmptySync) {
 TEST_F(ProfileSyncServiceAutofillTest, HasNativeHasSyncNoMerge) {
   AutofillEntry native_entry(MakeAutofillEntry("native", "entry", 1));
   AutofillEntry sync_entry(MakeAutofillEntry("sync", "entry", 2));
-  AutoFillProfile sync_profile;
-  autofill_test::SetProfileInfo(&sync_profile,
-      "Billing", "Marion", "Mitchell", "Morrison",
-      "johnwayne@me.xyz", "Fox", "123 Zoo St.", "unit 5", "Hollywood", "CA",
-      "91601", "US", "12345678910", "01987654321");
-
-  AutoFillProfile* native_profile = new AutoFillProfile;
-  autofill_test::SetProfileInfo(native_profile,
-      "Work", "Josephine", "Alicia", "Saenz",
-      "joewayne@me.xyz", "Fox", "1212 Center.", "Bld. 5", "Orlando", "FL",
-      "32801", "US", "19482937549", "13502849239");
 
   std::vector<AutofillEntry> native_entries;
   native_entries.push_back(native_entry);
-  std::vector<AutoFillProfile*> native_profiles;
-  native_profiles.push_back(native_profile);
-
-  std::vector<AutoFillProfile> expected_profiles;
-  expected_profiles.push_back(*native_profile);
-  expected_profiles.push_back(sync_profile);
 
   EXPECT_CALL(web_database_, GetAllAutofillEntries(_)).
       WillOnce(DoAll(SetArgumentPointee<0>(native_entries), Return(true)));
-  EXPECT_CALL(web_database_, GetAutoFillProfiles(_)).
-      WillOnce(DoAll(SetArgumentPointee<0>(native_profiles), Return(true)));
+
+  EXPECT_CALL(web_database_, GetAutoFillProfiles(_)).WillOnce(Return(true));
+
   std::vector<AutofillEntry> sync_entries;
   sync_entries.push_back(sync_entry);
-  std::vector<AutoFillProfile> sync_profiles;
-  sync_profiles.push_back(sync_profile);
-  AddAutofillEntriesTask task(this, sync_entries, sync_profiles);
 
-  AutoFillProfile to_be_added(sync_profile);
+  AddAutofillTask<AutofillEntry> task(this, sync_entries);
+
   EXPECT_CALL(web_database_, UpdateAutofillEntries(ElementsAre(sync_entry))).
       WillOnce(Return(true));
-  // TODO(dhollowa): Duplicate removal when contents match but GUIDs don't.
-  // http://crbug.com/58813
-  EXPECT_CALL(web_database_, AddAutoFillProfile(_)).
-      WillOnce(Return(true));
+
   EXPECT_CALL(*personal_data_manager_, Refresh());
-  StartSyncService(&task, false);
+  StartSyncService(&task, false, syncable::AUTOFILL);
   ASSERT_TRUE(task.success());
 
   std::set<AutofillEntry> expected_entries;
@@ -703,9 +734,6 @@ TEST_F(ProfileSyncServiceAutofillTest, HasNativeHasSyncNoMerge) {
                                                new_sync_entries.end());
 
   EXPECT_TRUE(expected_entries == new_sync_entries_set);
-  EXPECT_EQ(2U, new_sync_profiles.size());
-  EXPECT_EQ(0, expected_profiles[0].Compare(new_sync_profiles[0]));
-  EXPECT_EQ(0, expected_profiles[1].Compare(new_sync_profiles[1]));
 }
 
 TEST_F(ProfileSyncServiceAutofillTest, HasNativeHasSyncMergeEntry) {
@@ -720,14 +748,13 @@ TEST_F(ProfileSyncServiceAutofillTest, HasNativeHasSyncMergeEntry) {
   EXPECT_CALL(web_database_, GetAutoFillProfiles(_)).WillOnce(Return(true));
 
   std::vector<AutofillEntry> sync_entries;
-  std::vector<AutoFillProfile> sync_profiles;
   sync_entries.push_back(sync_entry);
-  AddAutofillEntriesTask task(this, sync_entries, sync_profiles);
+  AddAutofillTask<AutofillEntry> task(this, sync_entries);
 
   EXPECT_CALL(web_database_, UpdateAutofillEntries(ElementsAre(merged_entry))).
       WillOnce(Return(true));
   EXPECT_CALL(*personal_data_manager_, Refresh());
-  StartSyncService(&task, false);
+  StartSyncService(&task, false, syncable::AUTOFILL);
   ASSERT_TRUE(task.success());
 
   std::vector<AutofillEntry> new_sync_entries;
@@ -740,51 +767,89 @@ TEST_F(ProfileSyncServiceAutofillTest, HasNativeHasSyncMergeEntry) {
 
 TEST_F(ProfileSyncServiceAutofillTest, HasNativeHasSyncMergeProfile) {
   AutoFillProfile sync_profile;
-  autofill_test::SetProfileInfo(&sync_profile,
-      "Billing", "Marion", "Mitchell", "Morrison",
+  autofill_test::SetProfileInfoWithGuid(&sync_profile,
+      "{23355099-1170-4b71-8ED4-144470CC9EBE}", "Billing",
+      "Mitchell", "Morrison",
       "johnwayne@me.xyz", "Fox", "123 Zoo St.", "unit 5", "Hollywood", "CA",
       "91601", "US", "12345678910", "01987654321");
 
   AutoFillProfile* native_profile = new AutoFillProfile;
-  autofill_test::SetProfileInfo(native_profile,
-      "Billing", "Josephine", "Alicia", "Saenz",
+  autofill_test::SetProfileInfoWithGuid(native_profile,
+      "{23355099-1170-4b71-8ED4-144470CC9EBE}", "Billing", "Alicia", "Saenz",
       "joewayne@me.xyz", "Fox", "1212 Center.", "Bld. 5", "Orlando", "FL",
       "32801", "US", "19482937549", "13502849239");
 
   std::vector<AutoFillProfile*> native_profiles;
   native_profiles.push_back(native_profile);
-  EXPECT_CALL(web_database_, GetAllAutofillEntries(_)). WillOnce(Return(true));
   EXPECT_CALL(web_database_, GetAutoFillProfiles(_)).
       WillOnce(DoAll(SetArgumentPointee<0>(native_profiles), Return(true)));
 
-  std::vector<AutofillEntry> sync_entries;
   std::vector<AutoFillProfile> sync_profiles;
   sync_profiles.push_back(sync_profile);
-  AddAutofillEntriesTask task(this, sync_entries, sync_profiles);
+  AddAutofillTask<AutoFillProfile> task(this, sync_profiles);
 
-  // TODO(dhollowa): Duplicate removal when contents match but GUIDs don't.
-  // http://crbug.com/58813
   EXPECT_CALL(web_database_, UpdateAutoFillProfile(_)).
       WillOnce(Return(true));
   EXPECT_CALL(*personal_data_manager_, Refresh());
-  StartSyncService(&task, false);
+  StartSyncService(&task, false, syncable::AUTOFILL_PROFILE);
   ASSERT_TRUE(task.success());
 
-  std::vector<AutofillEntry> new_sync_entries;
   std::vector<AutoFillProfile> new_sync_profiles;
-  ASSERT_TRUE(GetAutofillEntriesFromSyncDB(&new_sync_entries,
-                                           &new_sync_profiles));
+  ASSERT_TRUE(GetAutofillProfilesFromSyncDBUnderProfileNode(
+      &new_sync_profiles));
   ASSERT_EQ(1U, new_sync_profiles.size());
   EXPECT_EQ(0, sync_profile.Compare(new_sync_profiles[0]));
 }
 
+TEST_F(ProfileSyncServiceAutofillTest, MergeProfileWithDifferentGuid) {
+  AutoFillProfile sync_profile;
+
+  autofill_test::SetProfileInfoWithGuid(&sync_profile,
+      "{23355099-1170-4b71-8ED4-144470CC9EBE}", "Billing",
+      "Mitchell", "Morrison",
+      "johnwayne@me.xyz", "Fox", "123 Zoo St.", "unit 5", "Hollywood", "CA",
+      "91601", "US", "12345678910", "01987654321");
+
+  string native_guid = "{EDC609ED-7EEE-4f27-B00C-423242A9C44B}";
+  AutoFillProfile* native_profile = new AutoFillProfile;
+  autofill_test::SetProfileInfoWithGuid(native_profile,
+      native_guid.c_str(), "Billing",
+      "Mitchell", "Morrison",
+      "johnwayne@me.xyz", "Fox", "123 Zoo St.", "unit 5", "Hollywood", "CA",
+      "91601", "US", "12345678910", "01987654321");
+
+  std::vector<AutoFillProfile*> native_profiles;
+  native_profiles.push_back(native_profile);
+  EXPECT_CALL(web_database_, GetAutoFillProfiles(_)).
+      WillOnce(DoAll(SetArgumentPointee<0>(native_profiles), Return(true)));
+
+  std::vector<AutoFillProfile> sync_profiles;
+  sync_profiles.push_back(sync_profile);
+  AddAutofillTask<AutoFillProfile> task(this, sync_profiles);
+
+  EXPECT_CALL(web_database_, AddAutoFillProfile(_)).
+      WillOnce(Return(true));
+  EXPECT_CALL(web_database_, RemoveAutoFillProfile(native_guid)).
+      WillOnce(Return(true));
+  EXPECT_CALL(*personal_data_manager_, Refresh());
+  StartSyncService(&task, false, syncable::AUTOFILL_PROFILE);
+  ASSERT_TRUE(task.success());
+
+  std::vector<AutoFillProfile> new_sync_profiles;
+  ASSERT_TRUE(GetAutofillProfilesFromSyncDBUnderProfileNode(
+      &new_sync_profiles));
+  ASSERT_EQ(1U, new_sync_profiles.size());
+  EXPECT_EQ(0, sync_profile.Compare(new_sync_profiles[0]));
+  EXPECT_EQ(sync_profile.guid(), new_sync_profiles[0].guid());
+}
+
 TEST_F(ProfileSyncServiceAutofillTest, ProcessUserChangeAddEntry) {
   EXPECT_CALL(web_database_, GetAllAutofillEntries(_)).WillOnce(Return(true));
   EXPECT_CALL(web_database_, GetAutoFillProfiles(_)).WillOnce(Return(true));
   EXPECT_CALL(*personal_data_manager_, Refresh());
   SetIdleChangeProcessorExpectations();
   CreateRootTask task(this, syncable::AUTOFILL);
-  StartSyncService(&task, false);
+  StartSyncService(&task, false, syncable::AUTOFILL);
   ASSERT_TRUE(task.success());
 
   AutofillEntry added_entry(MakeAutofillEntry("added", "entry", 1));
@@ -809,89 +874,33 @@ TEST_F(ProfileSyncServiceAutofillTest, ProcessUserChangeAddEntry) {
 }
 
 TEST_F(ProfileSyncServiceAutofillTest, ProcessUserChangeAddProfile) {
-  EXPECT_CALL(web_database_, GetAllAutofillEntries(_)).WillOnce(Return(true));
   EXPECT_CALL(web_database_, GetAutoFillProfiles(_)).WillOnce(Return(true));
   EXPECT_CALL(*personal_data_manager_, Refresh());
   SetIdleChangeProcessorExpectations();
-  CreateRootTask task(this, syncable::AUTOFILL);
-  StartSyncService(&task, false);
+  CreateRootTask task(this, syncable::AUTOFILL_PROFILE);
+  StartSyncService(&task, false, syncable::AUTOFILL_PROFILE);
   ASSERT_TRUE(task.success());
 
   AutoFillProfile added_profile;
-  autofill_test::SetProfileInfo(&added_profile,
-      "Billing", "Josephine", "Alicia", "Saenz",
+  autofill_test::SetProfileInfoWithGuid(&added_profile,
+      "{D6ADA912-D374-4c0a-917D-F5C8EBE43011}", "Josephine", "Alicia", "Saenz",
       "joewayne@me.xyz", "Fox", "1212 Center.", "Bld. 5", "Orlando", "FL",
       "32801", "US", "19482937549", "13502849239");
 
-  AutofillProfileChange change(AutofillProfileChange::ADD,
-      added_profile.Label(), &added_profile, string16());
+  AutofillProfileChangeGUID change(AutofillProfileChangeGUID::ADD,
+      added_profile.guid(), &added_profile);
   scoped_refptr<ThreadNotifier> notifier(new ThreadNotifier(&db_thread_));
-  notifier->Notify(NotificationType::AUTOFILL_PROFILE_CHANGED,
+  notifier->Notify(NotificationType::AUTOFILL_PROFILE_CHANGED_GUID,
                    Source<WebDataService>(web_data_service_.get()),
-                   Details<AutofillProfileChange>(&change));
+                   Details<AutofillProfileChangeGUID>(&change));
 
-  std::vector<AutofillEntry> new_sync_entries;
   std::vector<AutoFillProfile> new_sync_profiles;
-  ASSERT_TRUE(GetAutofillEntriesFromSyncDB(&new_sync_entries,
-                                           &new_sync_profiles));
+  ASSERT_TRUE(GetAutofillProfilesFromSyncDBUnderProfileNode(
+      &new_sync_profiles));
   ASSERT_EQ(1U, new_sync_profiles.size());
   EXPECT_EQ(0, added_profile.Compare(new_sync_profiles[0]));
 }
 
-TEST_F(ProfileSyncServiceAutofillTest, ProcessUserChangeAddProfileConflict) {
-  AutoFillProfile sync_profile;
-  autofill_test::SetProfileInfo(&sync_profile,
-      "Billing", "Marion", "Mitchell", "Morrison",
-      "johnwayne@me.xyz", "Fox", "123 Zoo St.", "unit 5", "Hollywood", "CA",
-      "91601", "US", "12345678910", "01987654321");
-
-  std::vector<AutofillEntry> sync_entries;
-  std::vector<AutoFillProfile> sync_profiles;
-  sync_profiles.push_back(sync_profile);
-  AddAutofillEntriesTask task(this, sync_entries, sync_profiles);
-
-  EXPECT_CALL(web_database_, GetAllAutofillEntries(_)).WillOnce(Return(true));
-  EXPECT_CALL(web_database_, GetAutoFillProfiles(_)).WillOnce(Return(true));
-  // TODO(dhollowa): Duplicate removal when contents match but GUIDs don't.
-  // http://crbug.com/58813
-  EXPECT_CALL(web_database_, AddAutoFillProfile(_)).
-              WillOnce(Return(true));
-  EXPECT_CALL(*personal_data_manager_, Refresh());
-  SetIdleChangeProcessorExpectations();
-  StartSyncService(&task, false);
-  ASSERT_TRUE(task.success());
-
-  AutoFillProfile added_profile;
-  autofill_test::SetProfileInfo(&added_profile,
-      "Billing", "Josephine", "Alicia", "Saenz",
-      "joewayne@me.xyz", "Fox", "1212 Center.", "Bld. 5", "Orlando", "FL",
-      "32801", "US", "19482937549", "13502849239");
-
-  AutofillProfileChange change(AutofillProfileChange::ADD,
-      added_profile.Label(), &added_profile, string16());
-
-  AutoFillProfile relabelled_profile;
-  EXPECT_CALL(web_database_, UpdateAutoFillProfile(
-      ProfileMatchesExceptLabel(added_profile))).
-      WillOnce(DoAll(SaveArg<0>(&relabelled_profile), Return(true)));
-  EXPECT_CALL(*personal_data_manager_, Refresh());
-
-  scoped_refptr<ThreadNotifier> notifier(new ThreadNotifier(&db_thread_));
-  notifier->Notify(NotificationType::AUTOFILL_PROFILE_CHANGED,
-                   Source<WebDataService>(web_data_service_.get()),
-                   Details<AutofillProfileChange>(&change));
-
-  std::vector<AutofillEntry> new_sync_entries;
-  std::vector<AutoFillProfile> new_sync_profiles;
-  ASSERT_TRUE(GetAutofillEntriesFromSyncDB(&new_sync_entries,
-                                           &new_sync_profiles));
-  ASSERT_EQ(2U, new_sync_profiles.size());
-  EXPECT_EQ(0, sync_profile.Compare(new_sync_profiles[1]));
-  EXPECT_TRUE(ProfilesMatchExceptLabelImpl(added_profile,
-                                           new_sync_profiles[0]));
-  EXPECT_EQ(new_sync_profiles[0].Label(), relabelled_profile.Label());
-}
-
 TEST_F(ProfileSyncServiceAutofillTest, ProcessUserChangeUpdateEntry) {
   AutofillEntry original_entry(MakeAutofillEntry("my", "entry", 1));
   std::vector<AutofillEntry> original_entries;
@@ -902,7 +911,7 @@ TEST_F(ProfileSyncServiceAutofillTest, ProcessUserChangeUpdateEntry) {
   EXPECT_CALL(web_database_, GetAutoFillProfiles(_)).WillOnce(Return(true));
   EXPECT_CALL(*personal_data_manager_, Refresh());
   CreateRootTask task(this, syncable::AUTOFILL);
-  StartSyncService(&task, false);
+  StartSyncService(&task, false, syncable::AUTOFILL);
   ASSERT_TRUE(task.success());
 
   AutofillEntry updated_entry(MakeAutofillEntry("my", "entry", 1, 2));
@@ -928,147 +937,6 @@ TEST_F(ProfileSyncServiceAutofillTest, ProcessUserChangeUpdateEntry) {
 }
 
 
-TEST_F(ProfileSyncServiceAutofillTest, ProcessUserChangeUpdateProfile) {
-  AutoFillProfile* native_profile = new AutoFillProfile;
-  autofill_test::SetProfileInfo(native_profile,
-      "Billing", "Josephine", "Alicia", "Saenz",
-      "joewayne@me.xyz", "Fox", "1212 Center.", "Bld. 5", "Orlando", "FL",
-      "32801", "US", "19482937549", "13502849239");
-  std::vector<AutoFillProfile*> native_profiles;
-  native_profiles.push_back(native_profile);
-  EXPECT_CALL(web_database_, GetAllAutofillEntries(_)). WillOnce(Return(true));
-  EXPECT_CALL(web_database_, GetAutoFillProfiles(_)).
-      WillOnce(DoAll(SetArgumentPointee<0>(native_profiles), Return(true)));
-  EXPECT_CALL(*personal_data_manager_, Refresh());
-  CreateRootTask task(this, syncable::AUTOFILL);
-  StartSyncService(&task, false);
-  ASSERT_TRUE(task.success());
-
-  AutoFillProfile update_profile;
-  autofill_test::SetProfileInfo(&update_profile,
-      "Billing", "Changin'", "Mah", "Namez",
-      "joewayne@me.xyz", "Fox", "1212 Center.", "Bld. 5", "Orlando", "FL",
-      "32801", "US", "19482937549", "13502849239");
-
-  AutofillProfileChange change(AutofillProfileChange::UPDATE,
-                               update_profile.Label(), &update_profile,
-                               ASCIIToUTF16("Billing"));
-  scoped_refptr<ThreadNotifier> notifier(new ThreadNotifier(&db_thread_));
-  notifier->Notify(NotificationType::AUTOFILL_PROFILE_CHANGED,
-                   Source<WebDataService>(web_data_service_.get()),
-                   Details<AutofillProfileChange>(&change));
-
-  std::vector<AutofillEntry> new_sync_entries;
-  std::vector<AutoFillProfile> new_sync_profiles;
-  ASSERT_TRUE(GetAutofillEntriesFromSyncDB(&new_sync_entries,
-                                           &new_sync_profiles));
-  ASSERT_EQ(1U, new_sync_profiles.size());
-  EXPECT_EQ(0, update_profile.Compare(new_sync_profiles[0]));
-}
-
-TEST_F(ProfileSyncServiceAutofillTest, ProcessUserChangeUpdateProfileRelabel) {
-  AutoFillProfile* native_profile = new AutoFillProfile;
-  autofill_test::SetProfileInfo(native_profile,
-      "Billing", "Josephine", "Alicia", "Saenz",
-      "joewayne@me.xyz", "Fox", "1212 Center.", "Bld. 5", "Orlando", "FL",
-      "32801", "US", "19482937549", "13502849239");
-  std::vector<AutoFillProfile*> native_profiles;
-  native_profiles.push_back(native_profile);
-  EXPECT_CALL(web_database_, GetAllAutofillEntries(_)). WillOnce(Return(true));
-  EXPECT_CALL(web_database_, GetAutoFillProfiles(_)).
-      WillOnce(DoAll(SetArgumentPointee<0>(native_profiles), Return(true)));
-  EXPECT_CALL(*personal_data_manager_, Refresh());
-  CreateRootTask task(this, syncable::AUTOFILL);
-  StartSyncService(&task, false);
-  ASSERT_TRUE(task.success());
-
-  AutoFillProfile update_profile;
-  autofill_test::SetProfileInfo(&update_profile,
-      "TRYIN 2 FOOL U", "Josephine", "Alicia", "Saenz",
-      "joewayne@me.xyz", "Fox", "1212 Center.", "Bld. 5", "Orlando", "FL",
-      "32801", "US", "19482937549", "13502849239");
-
-  AutofillProfileChange change(AutofillProfileChange::UPDATE,
-                               update_profile.Label(), &update_profile,
-                               ASCIIToUTF16("Billing"));
-  scoped_refptr<ThreadNotifier> notifier(new ThreadNotifier(&db_thread_));
-  notifier->Notify(NotificationType::AUTOFILL_PROFILE_CHANGED,
-                   Source<WebDataService>(web_data_service_.get()),
-                   Details<AutofillProfileChange>(&change));
-
-  std::vector<AutofillEntry> new_sync_entries;
-  std::vector<AutoFillProfile> new_sync_profiles;
-  ASSERT_TRUE(GetAutofillEntriesFromSyncDB(&new_sync_entries,
-                                           &new_sync_profiles));
-  ASSERT_EQ(1U, new_sync_profiles.size());
-  EXPECT_EQ(0, update_profile.Compare(new_sync_profiles[0]));
-}
-
-TEST_F(ProfileSyncServiceAutofillTest,
-       ProcessUserChangeUpdateProfileRelabelConflict) {
-  std::vector<AutoFillProfile*> native_profiles;
-  native_profiles.push_back(new AutoFillProfile);
-  native_profiles.push_back(new AutoFillProfile);
-  autofill_test::SetProfileInfo(native_profiles[0],
-      "Billing", "Josephine", "Alicia", "Saenz",
-      "joewayne@me.xyz", "Fox", "1212 Center.", "Bld. 5", "Orlando", "FL",
-      "32801", "US", "19482937549", "13502849239");
-  autofill_test::SetProfileInfo(native_profiles[1],
-      "ExistingLabel", "Marion", "Mitchell", "Morrison",
-      "johnwayne@me.xyz", "Fox", "123 Zoo St.", "unit 5", "Hollywood", "CA",
-      "91601", "US", "12345678910", "01987654321");
-  AutoFillProfile marion(*native_profiles[1]);
-  AutoFillProfile josephine(*native_profiles[0]);
-
-  EXPECT_CALL(web_database_, GetAllAutofillEntries(_)). WillOnce(Return(true));
-  EXPECT_CALL(web_database_, GetAutoFillProfiles(_)).
-      WillOnce(DoAll(SetArgumentPointee<0>(native_profiles), Return(true)));
-  EXPECT_CALL(*personal_data_manager_, Refresh());
-  CreateRootTask task(this, syncable::AUTOFILL);
-  StartSyncService(&task, false);
-  ASSERT_TRUE(task.success());
-  MessageLoop::current()->RunAllPending();
-  Mock::VerifyAndClearExpectations(&web_database_);
-  native_profiles.clear();  // Contents freed.
-
-  // Update josephine twice with marion's label.  The second time ought to be
-  // idempotent, settling on the same name and not triggering a sync upload.
-  for (int pass = 0; pass < 2; ++pass) {
-    AutoFillProfile josephine_update(josephine);
-    // TODO(dhollowa): Replace with |AutoFillProfile::set_guid|.
-    // http://crbug.com/58813
-    josephine_update.set_label(ASCIIToUTF16("ExistingLabel"));
-
-    AutoFillProfile relabelled_profile;
-    EXPECT_CALL(web_database_, UpdateAutoFillProfile(
-        ProfileMatchesExceptLabel(josephine_update))).
-        WillOnce(DoAll(SaveArg<0>(&relabelled_profile), Return(true)));
-    EXPECT_CALL(*personal_data_manager_, Refresh());
-
-    AutofillProfileChange change(AutofillProfileChange::UPDATE,
-                                 josephine_update.Label(), &josephine_update,
-                                 josephine.Label());
-    scoped_refptr<ThreadNotifier> notifier(new ThreadNotifier(&db_thread_));
-    notifier->Notify(NotificationType::AUTOFILL_PROFILE_CHANGED,
-                     Source<WebDataService>(web_data_service_.get()),
-                     Details<AutofillProfileChange>(&change));
-    MessageLoop::current()->RunAllPending();  // Run the Refresh task.
-    Mock::VerifyAndClearExpectations(&web_database_);
-
-    std::vector<AutofillEntry> new_sync_entries;
-    std::vector<AutoFillProfile> new_sync_profiles;
-    ASSERT_TRUE(GetAutofillEntriesFromSyncDB(&new_sync_entries,
-                                             &new_sync_profiles));
-    ASSERT_EQ(2U, new_sync_profiles.size());
-    EXPECT_EQ(0, marion.Compare(new_sync_profiles[1]));
-    EXPECT_TRUE(ProfilesMatchExceptLabelImpl(josephine_update,
-                                             new_sync_profiles[0]));
-    EXPECT_EQ(ASCIIToUTF16("ExistingLabel2"), new_sync_profiles[0].Label());
-    EXPECT_EQ(ASCIIToUTF16("ExistingLabel2"), relabelled_profile.Label());
-    josephine = relabelled_profile;
-  }
-}
-
 TEST_F(ProfileSyncServiceAutofillTest, ProcessUserChangeRemoveEntry) {
   AutofillEntry original_entry(MakeAutofillEntry("my", "entry", 1));
   std::vector<AutofillEntry> original_entries;
@@ -1079,7 +947,7 @@ TEST_F(ProfileSyncServiceAutofillTest, ProcessUserChangeRemoveEntry) {
   EXPECT_CALL(web_database_, GetAutoFillProfiles(_)).WillOnce(Return(true));
   EXPECT_CALL(*personal_data_manager_, Refresh());
   CreateRootTask task(this, syncable::AUTOFILL);
-  StartSyncService(&task, false);
+  StartSyncService(&task, false, syncable::AUTOFILL);
   ASSERT_TRUE(task.success());
 
   AutofillChangeList changes;
@@ -1099,42 +967,39 @@ TEST_F(ProfileSyncServiceAutofillTest, ProcessUserChangeRemoveEntry) {
 
 TEST_F(ProfileSyncServiceAutofillTest, ProcessUserChangeRemoveProfile) {
   AutoFillProfile sync_profile;
-  autofill_test::SetProfileInfo(&sync_profile,
-      "Billing", "Josephine", "Alicia", "Saenz",
+  autofill_test::SetProfileInfoWithGuid(&sync_profile,
+      "{3BA5FA1B-1EC4-4bb3-9B57-EC92BE3C1A09}", "Josephine", "Alicia", "Saenz",
       "joewayne@me.xyz", "Fox", "1212 Center.", "Bld. 5", "Orlando", "FL",
       "32801", "US", "19482937549", "13502849239");
   AutoFillProfile* native_profile = new AutoFillProfile;
-  autofill_test::SetProfileInfo(native_profile,
-      "Billing", "Josephine", "Alicia", "Saenz",
+  autofill_test::SetProfileInfoWithGuid(native_profile,
+      "{3BA5FA1B-1EC4-4bb3-9B57-EC92BE3C1A09}", "Josephine", "Alicia", "Saenz",
       "joewayne@me.xyz", "Fox", "1212 Center.", "Bld. 5", "Orlando", "FL",
       "32801", "US", "19482937549", "13502849239");
 
   std::vector<AutoFillProfile*> native_profiles;
   native_profiles.push_back(native_profile);
-  EXPECT_CALL(web_database_, GetAllAutofillEntries(_)). WillOnce(Return(true));
   EXPECT_CALL(web_database_, GetAutoFillProfiles(_)).
       WillOnce(DoAll(SetArgumentPointee<0>(native_profiles), Return(true)));
 
-  std::vector<AutofillEntry> sync_entries;
   std::vector<AutoFillProfile> sync_profiles;
   sync_profiles.push_back(sync_profile);
-  AddAutofillEntriesTask task(this, sync_entries, sync_profiles);
+  AddAutofillTask<AutoFillProfile> task(this, sync_profiles);
   EXPECT_CALL(*personal_data_manager_, Refresh());
-  StartSyncService(&task, false);
+  StartSyncService(&task, false, syncable::AUTOFILL_PROFILE);
   ASSERT_TRUE(task.success());
 
-  AutofillProfileChange change(AutofillProfileChange::REMOVE,
-                               sync_profile.Label(), NULL, string16());
+  AutofillProfileChangeGUID change(AutofillProfileChangeGUID::REMOVE,
+                               sync_profile.guid(), NULL);
   scoped_refptr<ThreadNotifier> notifier(new ThreadNotifier(&db_thread_));
-  notifier->Notify(NotificationType::AUTOFILL_PROFILE_CHANGED,
+  notifier->Notify(NotificationType::AUTOFILL_PROFILE_CHANGED_GUID,
                    Source<WebDataService>(web_data_service_.get()),
-                   Details<AutofillProfileChange>(&change));
+                   Details<AutofillProfileChangeGUID>(&change));
 
-  std::vector<AutofillEntry> new_sync_entries;
   std::vector<AutoFillProfile> new_sync_profiles;
-  ASSERT_TRUE(GetAutofillEntriesFromSyncDB(&new_sync_entries,
-                                           &new_sync_profiles));
-  ASSERT_EQ(0U, new_sync_entries.size());
+  ASSERT_TRUE(GetAutofillProfilesFromSyncDBUnderProfileNode(
+      &new_sync_profiles));
+  ASSERT_EQ(0U, new_sync_profiles.size());
 }
 
 TEST_F(ProfileSyncServiceAutofillTest, ProcessUserChangeError) {
@@ -1142,7 +1007,7 @@ TEST_F(ProfileSyncServiceAutofillTest, ProcessUserChangeError) {
   EXPECT_CALL(web_database_, GetAutoFillProfiles(_)).WillOnce(Return(true));
   EXPECT_CALL(*personal_data_manager_, Refresh());
   CreateRootTask task(this, syncable::AUTOFILL);
-  StartSyncService(&task, false);
+  StartSyncService(&task, false, syncable::AUTOFILL);
   ASSERT_TRUE(task.success());
 
   // Inject an evil entry into the sync db to conflict with the same
@@ -1179,7 +1044,7 @@ TEST_F(ProfileSyncServiceAutofillTest, DISABLED_ServerChangeRace) {
       WillRepeatedly(Return(true));
   EXPECT_CALL(*personal_data_manager_, Refresh()).Times(3);
   CreateRootTask task(this, syncable::AUTOFILL);
-  StartSyncService(&task, false);
+  StartSyncService(&task, false, syncable::AUTOFILL);
   ASSERT_TRUE(task.success());
 
   // (true, false) means we have to reset after |Signal|, init to unsignaled.
diff --git a/chrome/browser/sync/profile_sync_service_harness.cc b/chrome/browser/sync/profile_sync_service_harness.cc
index d275147..14fba6e 100644
--- a/chrome/browser/sync/profile_sync_service_harness.cc
+++ b/chrome/browser/sync/profile_sync_service_harness.cc
@@ -2,12 +2,16 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#include "chrome/browser/sync/profile_sync_service_harness.h"
+
+#include <algorithm>
+#include <vector>
+
 #include "base/message_loop.h"
 #include "chrome/browser/prefs/pref_service.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/net/gaia/token_service.h"
 #include "chrome/browser/sync/glue/sync_backend_host.h"
-#include "chrome/browser/sync/profile_sync_service_harness.h"
 #include "chrome/browser/sync/sessions/session_state.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/common/net/gaia/gaia_constants.h"
@@ -90,8 +94,7 @@ ProfileSyncServiceHarness::ProfileSyncServiceHarness(
     : wait_state_(INITIAL_WAIT_STATE),
       profile_(profile),
       service_(NULL),
-      last_timestamp_(0),
-      min_timestamp_needed_(kMinTimestampNeededNone),
+      timestamp_match_partner_(NULL),
       username_(username),
       password_(password),
       id_(id) {
@@ -263,11 +266,14 @@ bool ProfileSyncServiceHarness::RunStateChangeMachine() {
     }
     case WAITING_FOR_UPDATES: {
       LogClientInfo("WAITING_FOR_UPDATES");
-      if (!IsSynced() || GetUpdatedTimestamp() < min_timestamp_needed_) {
-        // The client is not yet fully synced. Continue waiting until the client
-        // is at the required minimum timestamp.
+      DCHECK(timestamp_match_partner_);
+      if (!MatchesOtherClient(timestamp_match_partner_)) {
+        // The client is not yet fully synced; keep waiting until we converge.
         break;
       }
+      timestamp_match_partner_->service()->RemoveObserver(this);
+      timestamp_match_partner_ = NULL;
+
       SignalStateCompleteWithNextState(FULLY_SYNCED);
       break;
     }
@@ -353,7 +359,7 @@ bool ProfileSyncServiceHarness::AwaitMutualSyncCycleCompletion(
   LogClientInfo("AwaitMutualSyncCycleCompletion");
   if (!AwaitSyncCycleCompletion("Sync cycle completion on active client."))
     return false;
-  return partner->WaitUntilTimestampIsAtLeast(last_timestamp_,
+  return partner->WaitUntilTimestampMatches(this,
       "Sync cycle completion on passive client.");
 }
 
@@ -367,7 +373,7 @@ bool ProfileSyncServiceHarness::AwaitGroupSyncCycleCompletion(
       partners.begin(); it != partners.end(); ++it) {
     if ((this != *it) && ((*it)->wait_state_ != SYNC_DISABLED)) {
       return_value = return_value &&
-          (*it)->WaitUntilTimestampIsAtLeast(last_timestamp_,
+          (*it)->WaitUntilTimestampMatches(this,
           "Sync cycle completion on partner client.");
     }
   }
@@ -388,20 +394,21 @@ bool ProfileSyncServiceHarness::AwaitQuiescence(
   return return_value;
 }
 
-bool ProfileSyncServiceHarness::WaitUntilTimestampIsAtLeast(
-    int64 timestamp, const std::string& reason) {
-  LogClientInfo("WaitUntilTimestampIsAtLeast");
+bool ProfileSyncServiceHarness::WaitUntilTimestampMatches(
+    ProfileSyncServiceHarness* partner, const std::string& reason) {
+  LogClientInfo("WaitUntilTimestampMatches");
   if (wait_state_ == SYNC_DISABLED) {
     LOG(ERROR) << "Sync disabled for Client " << id_ << ".";
     return false;
   }
-  min_timestamp_needed_ = timestamp;
-  if (GetUpdatedTimestamp() < min_timestamp_needed_) {
-    wait_state_ = WAITING_FOR_UPDATES;
-    return AwaitStatusChangeWithTimeout(kLiveSyncOperationTimeoutMs, reason);
-  } else {
+  DCHECK(!timestamp_match_partner_);
+  if (MatchesOtherClient(partner))
     return true;
-  }
+
+  timestamp_match_partner_ = partner;
+  partner->service()->AddObserver(this);
+  wait_state_ = WAITING_FOR_UPDATES;
+  return AwaitStatusChangeWithTimeout(kLiveSyncOperationTimeoutMs, reason);
 }
 
 bool ProfileSyncServiceHarness::AwaitStatusChangeWithTimeout(
@@ -424,8 +431,13 @@ bool ProfileSyncServiceHarness::AwaitStatusChangeWithTimeout(
       timeout_milliseconds);
   loop->Run();
   loop->SetNestableTasksAllowed(did_allow_nestable_tasks);
-  LogClientInfo("AwaitStatusChangeWithTimeout succeeded");
-  return timeout_signal->Abort();
+  if (timeout_signal->Abort()) {
+    LogClientInfo("AwaitStatusChangeWithTimeout succeeded");
+    return true;
+  } else {
+    LogClientInfo("AwaitStatusChangeWithTimeout timed out");
+    return false;
+  }
 }
 
 ProfileSyncService::Status ProfileSyncServiceHarness::GetStatus() {
@@ -449,6 +461,27 @@ bool ProfileSyncServiceHarness::IsSynced() {
           snap->unsynced_count == 0);
 }
 
+bool ProfileSyncServiceHarness::MatchesOtherClient(
+    ProfileSyncServiceHarness* partner) {
+  if (!IsSynced())
+    return false;
+
+  // Only look for a match if we have at least one enabled datatype in
+  // common with the partner client.
+  syncable::ModelTypeSet types, other_types, intersection_types;
+  service()->GetPreferredDataTypes(&types);
+  partner->service()->GetPreferredDataTypes(&other_types);
+  std::set_intersection(types.begin(), types.end(), other_types.begin(),
+                        other_types.end(),
+                        inserter(intersection_types,
+                                 intersection_types.begin()));
+  if (intersection_types.empty()) {
+    return true;
+  }
+  return partner->IsSynced() &&
+      partner->GetUpdatedTimestamp() == GetUpdatedTimestamp();
+}
+
 const SyncSessionSnapshot*
     ProfileSyncServiceHarness::GetLastSessionSnapshot() const {
   DCHECK(service_ != NULL) << "Sync service has not yet been set up.";
@@ -539,9 +572,7 @@ void ProfileSyncServiceHarness::DisableSyncForAllDatatypes() {
 int64 ProfileSyncServiceHarness::GetUpdatedTimestamp() {
   const SyncSessionSnapshot* snap = GetLastSessionSnapshot();
   DCHECK(snap != NULL) << "GetUpdatedTimestamp(): Sync snapshot is NULL.";
-  DCHECK_LE(last_timestamp_, snap->max_local_timestamp);
-  last_timestamp_ = snap->max_local_timestamp;
-  return last_timestamp_;
+  return snap->max_local_timestamp;
 }
 
 void ProfileSyncServiceHarness::LogClientInfo(std::string message) {
diff --git a/chrome/browser/sync/profile_sync_service_harness.h b/chrome/browser/sync/profile_sync_service_harness.h
index e3047af..064afe1 100644
--- a/chrome/browser/sync/profile_sync_service_harness.h
+++ b/chrome/browser/sync/profile_sync_service_harness.h
@@ -59,8 +59,9 @@ class ProfileSyncServiceHarness : public ProfileSyncServiceObserver {
   bool AwaitSyncCycleCompletion(const std::string& reason);
 
   // Blocks the caller until this harness has observed that the sync engine
-  // has "synced" up to at least the specified local timestamp.
-  bool WaitUntilTimestampIsAtLeast(int64 timestamp, const std::string& reason);
+  // has downloaded all the changes seen by the |partner| harness's client.
+  bool WaitUntilTimestampMatches(
+      ProfileSyncServiceHarness* partner, const std::string& reason);
 
   // Calling this acts as a barrier and blocks the caller until |this| and
   // |partner| have both completed a sync cycle.  When calling this method,
@@ -72,10 +73,9 @@ class ProfileSyncServiceHarness : public ProfileSyncServiceObserver {
   bool AwaitMutualSyncCycleCompletion(ProfileSyncServiceHarness* partner);
 
   // Blocks the caller until |this| completes its ongoing sync cycle and every
-  // other client in |partners| has a timestamp that is greater than or equal to
-  // the timestamp of |this|. Note: Use this method when exactly one client
-  // makes local change(s), and more than one client is waiting to receive those
-  // changes.
+  // other client in |partners| have achieved identical download progresses.
+  // Note: Use this method when exactly one client makes local change(s),
+  // and more than one client is waiting to receive those changes.
   bool AwaitGroupSyncCycleCompletion(
       std::vector<ProfileSyncServiceHarness*>& partners);
 
@@ -168,11 +168,14 @@ class ProfileSyncServiceHarness : public ProfileSyncServiceObserver {
   // Returns true if the sync client has no unsynced items.
   bool IsSynced();
 
+  // Returns true if this client has downloaded all the items that the
+  // other client has.
+  bool MatchesOtherClient(ProfileSyncServiceHarness* partner);
+
   // Logs message with relevant info about client's sync state (if available).
   void LogClientInfo(std::string message);
 
-  // Updates |last_timestamp_| with the timestamp of the current sync session.
-  // Returns the new value of |last_timestamp_|.
+  // Gets the current progress indicator of the current sync session.
   int64 GetUpdatedTimestamp();
 
   WaitState wait_state_;
@@ -180,15 +183,9 @@ class ProfileSyncServiceHarness : public ProfileSyncServiceObserver {
   Profile* profile_;
   ProfileSyncService* service_;
 
-  // This value tracks the max sync timestamp (e.g. synced-to revision) inside
-  // the sync engine.  It gets updated when a sync cycle ends and the session
-  // snapshot implies syncing is "done".
-  int64 last_timestamp_;
-
-  // The minimum value of the 'max_local_timestamp' member of a
-  // SyncSessionSnapshot we need to wait to observe in OnStateChanged when told
-  // to WaitUntilTimestampIsAtLeast(...).
-  int64 min_timestamp_needed_;
+  // The harness of the client whose update progress marker we're expecting
+  // eventually match.
+  ProfileSyncServiceHarness* timestamp_match_partner_;
 
   // Credentials used for GAIA authentication.
   std::string username_;
diff --git a/chrome/browser/sync/profile_sync_service_mock.cc b/chrome/browser/sync/profile_sync_service_mock.cc
new file mode 100644
index 0000000..8bfdb10
--- /dev/null
+++ b/chrome/browser/sync/profile_sync_service_mock.cc
@@ -0,0 +1,9 @@
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chrome/browser/sync/profile_sync_service_mock.h"
+
+ProfileSyncServiceMock::ProfileSyncServiceMock() {}
+
+ProfileSyncServiceMock::~ProfileSyncServiceMock() {}
diff --git a/chrome/browser/sync/profile_sync_service_mock.h b/chrome/browser/sync/profile_sync_service_mock.h
index a338631..32bff66 100644
--- a/chrome/browser/sync/profile_sync_service_mock.h
+++ b/chrome/browser/sync/profile_sync_service_mock.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
@@ -17,8 +17,8 @@
 
 class ProfileSyncServiceMock : public ProfileSyncService {
  public:
-  ProfileSyncServiceMock() {}
-  virtual ~ProfileSyncServiceMock() {}
+  ProfileSyncServiceMock();
+  virtual ~ProfileSyncServiceMock();
 
   MOCK_METHOD0(DisableForUser, void());
   MOCK_METHOD0(OnBackendInitialized, void());
diff --git a/chrome/browser/sync/profile_sync_service_session_unittest.cc b/chrome/browser/sync/profile_sync_service_session_unittest.cc
index 6242f0e..7f90cd6 100644
--- a/chrome/browser/sync/profile_sync_service_session_unittest.cc
+++ b/chrome/browser/sync/profile_sync_service_session_unittest.cc
@@ -170,16 +170,9 @@ TEST_F(ProfileSyncServiceSessionTest, WriteSessionToNode) {
   bool has_nodes;
   ASSERT_TRUE(model_associator_->SyncModelHasUserCreatedNodes(&has_nodes));
   ASSERT_TRUE(has_nodes);
-  ASSERT_TRUE(model_associator_->ChromeModelHasUserCreatedNodes(&has_nodes));
-  ASSERT_TRUE(has_nodes);
   std::string machine_tag = model_associator_->GetCurrentMachineTag();
-  int64 sync_id;
-  ASSERT_TRUE(model_associator_->GetSyncIdForTaggedNode(&machine_tag,
-      &sync_id));
-  ASSERT_EQ(model_associator_->GetSyncIdFromChromeId(machine_tag), sync_id);
-  scoped_ptr<const sync_pb::SessionSpecifics> sync_specifics(
-      model_associator_->GetChromeNodeFromSyncId(sync_id));
-  ASSERT_TRUE(sync_specifics != NULL);
+  int64 sync_id = model_associator_->GetSyncIdFromSessionTag(machine_tag);
+  ASSERT_NE(sync_api::kInvalidId, sync_id);
 
   // Check that we can get the correct session specifics back from the node.
   sync_api::ReadTransaction trans(sync_service_->
@@ -188,8 +181,10 @@ TEST_F(ProfileSyncServiceSessionTest, WriteSessionToNode) {
   ASSERT_TRUE(node.InitByClientTagLookup(syncable::SESSIONS,
       machine_tag));
   const sync_pb::SessionSpecifics& specifics(node.GetSessionSpecifics());
-  ASSERT_EQ(sync_specifics->session_tag(), specifics.session_tag());
   ASSERT_EQ(machine_tag, specifics.session_tag());
+  ASSERT_TRUE(specifics.has_header());
+  const sync_pb::SessionHeader& header_s = specifics.header();
+  ASSERT_EQ(0, header_s.window_size());
 }
 
 // Test that we can fill this machine's session, write it to a node,
@@ -208,51 +203,35 @@ TEST_F(ProfileSyncServiceSessionTest, WriteFilledSessionToNode) {
   AddTab(browser(), GURL("http://bar/1"));
   NavigateAndCommitActiveTab(GURL("http://bar/2"));
 
-  // Report a saved session, thus causing the ChangeProcessor to write to a
-  // node.
-  NotificationService::current()->Notify(
-      NotificationType::SESSION_SERVICE_SAVED,
-      Source<Profile>(profile()),
-      NotificationService::NoDetails());
+  ASSERT_TRUE(model_associator_->SyncModelHasUserCreatedNodes(&has_nodes));
+  ASSERT_TRUE(has_nodes);
   std::string machine_tag = model_associator_->GetCurrentMachineTag();
-  int64 sync_id;
-  ASSERT_TRUE(model_associator_->GetSyncIdForTaggedNode(&machine_tag,
-      &sync_id));
-  ASSERT_EQ(model_associator_->GetSyncIdFromChromeId(machine_tag), sync_id);
-  scoped_ptr<const sync_pb::SessionSpecifics> sync_specifics(
-      model_associator_->GetChromeNodeFromSyncId(sync_id));
-  ASSERT_TRUE(sync_specifics != NULL);
+  int64 sync_id = model_associator_->GetSyncIdFromSessionTag(machine_tag);
+  ASSERT_NE(sync_api::kInvalidId, sync_id);
 
   // Check that this machine's data is not included in the foreign windows.
-  ScopedVector<ForeignSession> foreign_sessions;
-  model_associator_->GetSessionData(&foreign_sessions.get());
+  std::vector<const ForeignSession*> foreign_sessions;
+  model_associator_->GetAllForeignSessions(&foreign_sessions);
   ASSERT_EQ(foreign_sessions.size(), 0U);
 
-  // Get the windows for this machine from the node and check that they were
+  // Get the tabs for this machine from the node and check that they were
   // filled.
-  sync_api::ReadTransaction trans(sync_service_->
-      backend()->GetUserShareHandle());
-  sync_api::ReadNode node(&trans);
-  ASSERT_TRUE(node.InitByClientTagLookup(syncable::SESSIONS,
-      machine_tag));
-  model_associator_->AppendForeignSessionWithID(sync_id,
-      &foreign_sessions.get(), &trans);
-  ASSERT_EQ(foreign_sessions.size(), 1U);
-  ASSERT_EQ(1U,  foreign_sessions[0]->windows.size());
-  ASSERT_EQ(2U, foreign_sessions[0]->windows[0]->tabs.size());
-  ASSERT_EQ(2U, foreign_sessions[0]->windows[0]->tabs[0]->navigations.size());
-  ASSERT_EQ(GURL("http://bar/1"),
-      foreign_sessions[0]->windows[0]->tabs[0]->navigations[0].virtual_url());
-  ASSERT_EQ(GURL("http://bar/2"),
-      foreign_sessions[0]->windows[0]->tabs[0]->navigations[1].virtual_url());
-  ASSERT_EQ(2U, foreign_sessions[0]->windows[0]->tabs[1]->navigations.size());
-  ASSERT_EQ(GURL("http://foo/1"),
-      foreign_sessions[0]->windows[0]->tabs[1]->navigations[0].virtual_url());
-  ASSERT_EQ(GURL("http://foo/2"),
-      foreign_sessions[0]->windows[0]->tabs[1]->navigations[1].virtual_url());
-  const sync_pb::SessionSpecifics& specifics(node.GetSessionSpecifics());
-  ASSERT_EQ(sync_specifics->session_tag(), specifics.session_tag());
-  ASSERT_EQ(machine_tag, specifics.session_tag());
+  SessionModelAssociator::TabLinksMap tab_map = model_associator_->tab_map_;
+  ASSERT_EQ(2U, tab_map.size());
+  // Tabs are ordered by sessionid in tab_map, so should be able to traverse
+  // the tree based on order of tabs created
+  SessionModelAssociator::TabLinksMap::iterator iter = tab_map.begin();
+  ASSERT_EQ(2, iter->second.tab()->controller().entry_count());
+  ASSERT_EQ(GURL("http://foo/1"), iter->second.tab()->controller().
+          GetEntryAtIndex(0)->virtual_url());
+  ASSERT_EQ(GURL("http://foo/2"), iter->second.tab()->controller().
+          GetEntryAtIndex(1)->virtual_url());
+  iter++;
+  ASSERT_EQ(2, iter->second.tab()->controller().entry_count());
+  ASSERT_EQ(GURL("http://bar/1"), iter->second.tab()->controller().
+      GetEntryAtIndex(0)->virtual_url());
+  ASSERT_EQ(GURL("http://bar/2"), iter->second.tab()->controller().
+      GetEntryAtIndex(1)->virtual_url());
 }
 
 // Test that we fail on a failed model association.
@@ -273,13 +252,18 @@ TEST_F(ProfileSyncServiceSessionTest, WriteForeignSessionToNode) {
   ASSERT_TRUE(has_nodes);
 
   // Fill an instance of session specifics with a foreign session's data.
-  sync_pb::SessionSpecifics specifics;
+  sync_pb::SessionSpecifics meta_specifics;
   std::string machine_tag = "session_sync123";
-  specifics.set_session_tag(machine_tag);
-  sync_pb::SessionWindow* window = specifics.add_session_window();
-  window->set_selected_tab_index(1);
-  window->set_browser_type(sync_pb::SessionWindow_BrowserType_TYPE_NORMAL);
-  sync_pb::SessionTab* tab = window->add_session_tab();
+  meta_specifics.set_session_tag(machine_tag);
+  sync_pb::SessionHeader* header_s = meta_specifics.mutable_header();
+  sync_pb::SessionWindow* window_s = header_s->add_window();
+  window_s->add_tab(0);
+  window_s->set_browser_type(sync_pb::SessionWindow_BrowserType_TYPE_NORMAL);
+  window_s->set_selected_tab_index(1);
+
+  sync_pb::SessionSpecifics tab_specifics;
+  tab_specifics.set_session_tag(machine_tag);
+  sync_pb::SessionTab* tab = tab_specifics.mutable_tab();
   tab->set_tab_visual_index(13);
   tab->set_current_navigation_index(3);
   tab->set_pinned(true);
@@ -293,25 +277,15 @@ TEST_F(ProfileSyncServiceSessionTest, WriteForeignSessionToNode) {
 
   // Update the server with the session specifics.
   {
-    sync_api::WriteTransaction trans(sync_service_->
-        backend()->GetUserShareHandle());
-    sync_api::ReadNode root(&trans);
-    ASSERT_TRUE(root.InitByTagLookup(kSessionsTag));
-    model_associator_->UpdateSyncModel(&specifics, &trans, &root);
-    model_associator_->UpdateFromSyncModel(&trans);
+    model_associator_->AssociateForeignSpecifics(meta_specifics, 0);
+    model_associator_->AssociateForeignSpecifics(tab_specifics, 0);
   }
 
-  // Check that the foreign session was written to a node and retrieve the data.
-  int64 sync_id;
-  ASSERT_TRUE(model_associator_->GetSyncIdForTaggedNode(&machine_tag,
-      &sync_id));
-  ASSERT_EQ(model_associator_->GetSyncIdFromChromeId(machine_tag), sync_id);
-  scoped_ptr<const sync_pb::SessionSpecifics> sync_specifics(
-      model_associator_->GetChromeNodeFromSyncId(sync_id));
-  ASSERT_TRUE(sync_specifics != NULL);
-  ScopedVector<ForeignSession> foreign_sessions;
-  model_associator_->GetSessionData(&foreign_sessions.get());
+  // Check that the foreign session was associated and retrieve the data.
+  std::vector<const ForeignSession*> foreign_sessions;
+  model_associator_->GetAllForeignSessions(&foreign_sessions);
   ASSERT_EQ(1U, foreign_sessions.size());
+  ASSERT_EQ(machine_tag, foreign_sessions[0]->foreign_session_tag);
   ASSERT_EQ(1U,  foreign_sessions[0]->windows.size());
   ASSERT_EQ(1U, foreign_sessions[0]->windows[0]->tabs.size());
   ASSERT_EQ(1U, foreign_sessions[0]->windows[0]->tabs[0]->navigations.size());
@@ -334,14 +308,6 @@ TEST_F(ProfileSyncServiceSessionTest, WriteForeignSessionToNode) {
       foreign_sessions[0]->windows[0]->tabs[0]->navigations[0].transition());
   ASSERT_EQ(GURL("http://foo/1"),
       foreign_sessions[0]->windows[0]->tabs[0]->navigations[0].virtual_url());
-  sync_api::WriteTransaction trans(sync_service_->
-      backend()->GetUserShareHandle());
-  sync_api::ReadNode node(&trans);
-  ASSERT_TRUE(node.InitByClientTagLookup(syncable::SESSIONS,
-      machine_tag));
-  const sync_pb::SessionSpecifics& specifics_(node.GetSessionSpecifics());
-  ASSERT_EQ(sync_specifics->session_tag(), specifics_.session_tag());
-  ASSERT_EQ(machine_tag, specifics_.session_tag());
 }
 
 // Test the DataTypeController on update.
@@ -349,7 +315,7 @@ TEST_F(ProfileSyncServiceSessionTest, UpdatedSyncNodeActionUpdate) {
   CreateRootTask task(this);
   ASSERT_TRUE(StartSyncService(&task, false));
   ASSERT_TRUE(task.success());
-  int64 node_id = model_associator_->GetSyncIdFromChromeId(
+  int64 node_id = model_associator_->GetSyncIdFromSessionTag(
       model_associator_->GetCurrentMachineTag());
   scoped_ptr<SyncManager::ChangeRecord> record(new SyncManager::ChangeRecord);
   record->action = SyncManager::ChangeRecord::ACTION_UPDATE;
@@ -368,7 +334,7 @@ TEST_F(ProfileSyncServiceSessionTest, UpdatedSyncNodeActionAdd) {
   ASSERT_TRUE(StartSyncService(&task, false));
   ASSERT_TRUE(task.success());
 
-  int64 node_id = model_associator_->GetSyncIdFromChromeId(
+  int64 node_id = model_associator_->GetSyncIdFromSessionTag(
       model_associator_->GetCurrentMachineTag());
   scoped_ptr<SyncManager::ChangeRecord> record(new SyncManager::ChangeRecord);
   record->action = SyncManager::ChangeRecord::ACTION_ADD;
@@ -387,7 +353,7 @@ TEST_F(ProfileSyncServiceSessionTest, UpdatedSyncNodeActionDelete) {
   ASSERT_TRUE(StartSyncService(&task, false));
   ASSERT_TRUE(task.success());
 
-  int64 node_id = model_associator_->GetSyncIdFromChromeId(
+  int64 node_id = model_associator_->GetSyncIdFromSessionTag(
       model_associator_->GetCurrentMachineTag());
   scoped_ptr<SyncManager::ChangeRecord> record(new SyncManager::ChangeRecord);
   record->action = SyncManager::ChangeRecord::ACTION_DELETE;
@@ -399,6 +365,64 @@ TEST_F(ProfileSyncServiceSessionTest, UpdatedSyncNodeActionDelete) {
   }
   ASSERT_TRUE(notified_of_update_);
 }
+// Test the TabNodePool when it starts off empty.
+TEST_F(ProfileSyncServiceSessionTest, TabNodePoolEmpty) {
+  CreateRootTask task(this);
+  ASSERT_TRUE(StartSyncService(&task, false));
+  ASSERT_TRUE(task.success());
+
+  std::vector<int64> node_ids;
+  ASSERT_EQ(0U, model_associator_->tab_pool_.capacity());
+  ASSERT_TRUE(model_associator_->tab_pool_.empty());
+  ASSERT_TRUE(model_associator_->tab_pool_.full());
+  const size_t num_ids = 10;
+  for (size_t i = 0; i < num_ids; ++i) {
+    int64 id = model_associator_->tab_pool_.GetFreeTabNode();
+    ASSERT_GT(id, -1);
+    node_ids.push_back(id);
+  }
+  ASSERT_EQ(num_ids, model_associator_->tab_pool_.capacity());
+  ASSERT_TRUE(model_associator_->tab_pool_.empty());
+  ASSERT_FALSE(model_associator_->tab_pool_.full());
+  for (size_t i = 0; i < num_ids; ++i) {
+    model_associator_->tab_pool_.FreeTabNode(node_ids[i]);
+  }
+  ASSERT_EQ(num_ids, model_associator_->tab_pool_.capacity());
+  ASSERT_FALSE(model_associator_->tab_pool_.empty());
+  ASSERT_TRUE(model_associator_->tab_pool_.full());
+}
+
+// Test the TabNodePool when it starts off with nodes
+TEST_F(ProfileSyncServiceSessionTest, TabNodePoolNonEmpty) {
+  CreateRootTask task(this);
+  ASSERT_TRUE(StartSyncService(&task, false));
+  ASSERT_TRUE(task.success());
+
+  const size_t num_starting_nodes = 3;
+  for (size_t i = 0; i < num_starting_nodes; ++i) {
+    model_associator_->tab_pool_.AddTabNode(i);
+  }
+
+  std::vector<int64> node_ids;
+  ASSERT_EQ(num_starting_nodes, model_associator_->tab_pool_.capacity());
+  ASSERT_FALSE(model_associator_->tab_pool_.empty());
+  ASSERT_TRUE(model_associator_->tab_pool_.full());
+  const size_t num_ids = 10;
+  for (size_t i = 0; i < num_ids; ++i) {
+    int64 id = model_associator_->tab_pool_.GetFreeTabNode();
+    ASSERT_GT(id, -1);
+    node_ids.push_back(id);
+  }
+  ASSERT_EQ(num_ids, model_associator_->tab_pool_.capacity());
+  ASSERT_TRUE(model_associator_->tab_pool_.empty());
+  ASSERT_FALSE(model_associator_->tab_pool_.full());
+  for (size_t i = 0; i < num_ids; ++i) {
+    model_associator_->tab_pool_.FreeTabNode(node_ids[i]);
+  }
+  ASSERT_EQ(num_ids, model_associator_->tab_pool_.capacity());
+  ASSERT_FALSE(model_associator_->tab_pool_.empty());
+  ASSERT_TRUE(model_associator_->tab_pool_.full());
+}
 
 }  // namespace browser_sync
 
diff --git a/chrome/browser/sync/profile_sync_service_typed_url_unittest.cc b/chrome/browser/sync/profile_sync_service_typed_url_unittest.cc
index 17795c6..98b70c0 100644
--- a/chrome/browser/sync/profile_sync_service_typed_url_unittest.cc
+++ b/chrome/browser/sync/profile_sync_service_typed_url_unittest.cc
@@ -8,7 +8,7 @@
 
 #include "base/ref_counted.h"
 #include "base/string16.h"
-#include "base/thread.h"
+#include "base/threading/thread.h"
 #include "base/time.h"
 #include "chrome/browser/history/history_backend.h"
 #include "chrome/browser/history/history_notifications.h"
diff --git a/chrome/browser/sync/profile_sync_test_util.h b/chrome/browser/sync/profile_sync_test_util.h
index f6e66ac..4e28efa 100644
--- a/chrome/browser/sync/profile_sync_test_util.h
+++ b/chrome/browser/sync/profile_sync_test_util.h
@@ -13,8 +13,8 @@
 #include "base/ref_counted.h"
 #include "base/scoped_ptr.h"
 #include "base/task.h"
-#include "base/thread.h"
-#include "base/waitable_event.h"
+#include "base/threading/thread.h"
+#include "base/synchronization/waitable_event.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/browser/browser_thread.h"
 #include "chrome/browser/webdata/web_database.h"
diff --git a/chrome/browser/sync/protocol/session_specifics.proto b/chrome/browser/sync/protocol/session_specifics.proto
index 050687d..5b00b35 100644
--- a/chrome/browser/sync/protocol/session_specifics.proto
+++ b/chrome/browser/sync/protocol/session_specifics.proto
@@ -13,14 +13,20 @@ package sync_pb;
 
 import "sync.proto";
 
-// Properties of session sync objects.
 message SessionSpecifics {
-  // Unique id for the session.
+  // Unique id for the client.
   optional string session_tag = 1;
+  optional SessionHeader header = 2;
+  optional SessionTab tab = 3;  
+}
+// Properties of session sync objects.
+message SessionHeader {
   // Each session is composed of windows.
-  repeated SessionWindow session_window = 2;
+  repeated SessionWindow window = 2;
 }
 message SessionWindow {
+  // Unique (to the owner) id for this window.
+  optional int32 window_id = 1;
   // Index of the selected tab in tabs; -1 if no tab is selected.
   optional int32 selected_tab_index = 2 [default = -1];
   // Type of the browser. Currently we only store browsers of type
@@ -30,22 +36,26 @@ message SessionWindow {
     TYPE_POPUP = 2;
   }
   optional BrowserType browser_type = 3 [default = TYPE_NORMAL];
-  // The tabs that compose a window.
-  repeated SessionTab session_tab= 4;
+  // The tabs that compose a window (correspond to tab id's).
+  repeated int32 tab = 4;
 }
 message SessionTab {
+  // Unique (to the owner) id for this tab.
+  optional int32 tab_id = 1;
+  // The unique id for the window this tab belongs to.
+  optional int32 window_id = 2;
   // Visual index of the tab within its window. There may be gaps in these
   // values.
-  optional int32 tab_visual_index = 2 [default = -1];
+  optional int32 tab_visual_index = 3 [default = -1];
   // Identifies the index of the current navigation in navigations. For
   // example, if this is 2 it means the current navigation is navigations[2].
-  optional int32 current_navigation_index = 3 [default = -1];
+  optional int32 current_navigation_index = 4 [default = -1];
   // True if the tab is pinned.
-  optional bool pinned = 4 [default = false];
+  optional bool pinned = 5 [default = false];
   // If non-empty, this tab is an app tab and this is the id of the extension.
-  optional string extension_app_id = 5;
+  optional string extension_app_id = 6;
   // Tabs are navigated, and the navigation data is here.
-  repeated TabNavigation navigation = 6;
+  repeated TabNavigation navigation = 7;
 }
 message TabNavigation {
   // The index in the NavigationController. If this is -1, it means this
diff --git a/chrome/browser/sync/resources/configure.html b/chrome/browser/sync/resources/configure.html
index 90a3491..b087169 100644
--- a/chrome/browser/sync/resources/configure.html
+++ b/chrome/browser/sync/resources/configure.html
@@ -83,13 +83,11 @@ form {
 }
 
 #sync-encryption-instructions {
-  margin-bottom: 10px;
-  line-height: 1.8em;
+  margin-bottom: 5px;
 }
 
 #sync-passphrase-warning {
-  font-style: italic;
-  line-height: 1.8em;
+  margin-bottom: 5px;
 }
 
 #encryption-tab-contents > .sync_item_show {
@@ -145,6 +143,26 @@ form {
   margin-right: 10px;
   margin-bottom: 10px;
 }
+.sync-section {
+  background: #EEE;
+  margin: 5px 0px;
+  padding: 6px;
+}
+
+#explicit-message {
+  margin-bottom: 5px;
+}
+
+#change-passphrase {
+  margin: 10px 0;
+  background: #EEE;
+  padding: 8px;
+}
+
+#clear-data-button {
+  margin-top: 10px;
+}
+
 html[dir='rtl'] .sync-footer {
   text-align: left;
   left: 0px;
@@ -254,9 +272,9 @@ html[os='mac'] input[type='submit'] {
           args.syncApps;
       document.getElementById("appsItem").className = "sync-item-show";
     } else {
-      document.getElementById("appsItem").className = "sync-item-hide";

-    }

-

+      document.getElementById("appsItem").className = "sync-item-hide";
+    }
+
     setCheckboxesToKeepEverythingSynced(args.keepEverythingSynced);
     if (args.sessionsRegistered) {
       document.getElementById("sessionsCheckbox").checked = args.syncSessions;
@@ -267,13 +285,18 @@ html[os='mac'] input[type='submit'] {
   }
 
   function setEncryptionCheckboxes(args) {
-    document.getElementById("usePassphraseCheckbox").checked =
-        args["usePassphrase"];
-
-    // The passphrase, once set, cannot be unset.
     if (args["usePassphrase"]) {
-      document.getElementById("usePassphraseCheckbox").disabled = true;
+      document.getElementById("explicit-option").checked = true;
+
+      // The passphrase, once set, cannot be unset, but we show a reset link.
+      document.getElementById("explicit-option").disabled = true;
+      document.getElementById("google-option").disabled = true;
+      document.getElementById("change-passphrase").style.display = "block";
+    } else {
+      document.getElementById("google-option").checked = true;
+      document.getElementById("change-passphrase").style.display = "none";
     }
+    switchToMode("");
   }
 
   function setErrorState(args) {
@@ -298,6 +321,8 @@ html[os='mac'] input[type='submit'] {
     }
   }
 
+
+
   // Returns true if at least one data type is enabled and no data types are
   // checked.  (If all data type checkboxes are disabled, it's because "keep
   // everything synced" is checked.)
@@ -328,6 +353,10 @@ html[os='mac'] input[type='submit'] {
     }
 
     var f = document.getElementById("chooseDataTypesForm");
+    if (!checkPassphraseMatch()) {
+      return false;
+    }
+
     var syncAll = f.keepEverythingSyncedRadio.checked;
     // These values need to be kept in sync with where they are read in
     // SyncSetupFlow::GetDataTypeChoiceData().
@@ -342,7 +371,8 @@ html[os='mac'] input[type='submit'] {
         "syncTypedUrls": syncAll || f.typedUrlsCheckbox.checked,
         "syncApps": syncAll || f.appsCheckbox.checked,
         "syncSessions": syncAll || f.sessionsCheckbox.checked,
-        "usePassphrase": document.getElementById("usePassphraseCheckbox").checked
+        "usePassphrase": (getRadioCheckedValue() == 'explicit'),
+        "passphrase": f.passphrase.value
     });
     chrome.send("Configure", [result]);
   }
@@ -354,15 +384,73 @@ html[os='mac'] input[type='submit'] {
       document.getElementById(currentTab + "-tab-contents").className =
           "sync-config-tab-contents-inactive";
     }
-    
+
     document.getElementById(newTab + "-tab").className =
         "sync-config-tab-active";
     document.getElementById(newTab + "-tab-contents").className =
         "sync-config-tab-contents-active";
-    
+
     currentTab = newTab;
   }
 
+  function switchToMode(mode) {
+    document.getElementById("section-explicit").style.display = "none";
+    document.getElementById("section-google").style.display = "none";
+
+    if (mode == "google") {
+      document.getElementById("section-google").style.display = "block";
+    } else if (mode =="explicit") {
+      document.getElementById("section-explicit").style.display = "block";
+    }
+  }
+
+  function getRadioCheckedValue() {
+    var f = document.getElementById("chooseDataTypesForm");
+    for (var i = 0; i < f.option.length; ++i) {
+      if (f.option[i].checked) {
+        return f.option[i].value;
+      }
+    }
+    return undefined;
+  }
+
+  function onRadioChange() {
+    switchToMode(getRadioCheckedValue());
+  }
+
+  function checkPassphraseMatch() {
+    var emptyError = document.getElementById("emptyerror");
+    var mismatchError = document.getElementById("mismatcherror");
+    emptyError.style.display = "none";
+    mismatchError.style.display = "none";
+
+    if (getRadioCheckedValue() != "explicit") {
+      return true;
+    }
+    var f = document.getElementById("chooseDataTypesForm");
+    if (f.passphrase.value.length == 0) {
+      emptyError.style.display = "block";
+      return false;
+    }
+    if (f.confirmpassphrase.value.length > 0 &&
+        f.confirmpassphrase.value != f.passphrase.value) {
+      mismatchError.style.display = "block";
+      return false;
+    }
+    return true;
+  }
+
+  function sendValuesAndClose() {
+    var result = JSON.stringify({"option": getRadioCheckedValue(),
+                                 "passphrase": f.passphrase.value});
+    chrome.send("FirstPassphrase", [result]);
+  }
+
+  function goToDashboard() {
+    chrome.send("GoToDashboard", [""]);
+    chrome.send("DialogClose", [""]);
+  }
+
 </script>
 </head>
 <body i18n-values=".style.fontFamily:fontfamily"
@@ -381,9 +469,9 @@ html[os='mac'] input[type='submit'] {
   </div>
   <div id="data-type-tab-contents" class="sync-config-tab-contents-inactive">
 
-    <div class="sync-header" 
+    <div class="sync-header"
          i18n-content="choosedatatypesheader"></div>
-    <div class="sync-choose_data_types_instructions" 
+    <div class="sync-choose_data_types_instructions"
          i18n-content="choosedatatypesinstructions"></div>
     <div class="sync-select-customization">
       <div class="sync-choice_radio">
@@ -395,7 +483,7 @@ html[os='mac'] input[type='submit'] {
         </label>
       </div>
       <div id="chooseDataTypes" class="sync-choice_radio">
-        <input id="chooseDataTypesRadio" type="radio" name="syncChooseDataTypes" 
+        <input id="chooseDataTypesRadio" type="radio" name="syncChooseDataTypes"
                onclick="setCheckboxesToKeepEverythingSynced(false)">
         <label for="chooseDataTypesRadio" i18n-content="choosedatatypes" ></label>
         <div id="chooseDataTypesBody">
@@ -403,49 +491,49 @@ html[os='mac'] input[type='submit'] {
             <!-- Apps -->
             <div class="sync-item-show" id="appsItem">
               <input id="appsCheckbox" name="dataTypeCheckbox" type="checkbox">
-              <label id="appsCheckboxLabel" name="dataTypeLabel" 
+              <label id="appsCheckboxLabel" name="dataTypeLabel"
                      for="appsCheckbox" i18n-content="apps"
                      i18n-values="title:apps"></label>
             </div>
             <!-- Autofill -->
             <div class="sync-item-show" id="autofillItem">
               <input id="autofillCheckbox" name="dataTypeCheckbox" type="checkbox">
-              <label id="autofillCheckboxLabel" name="dataTypeLabel" 
+              <label id="autofillCheckboxLabel" name="dataTypeLabel"
                      for="autofillCheckbox" i18n-content="autofill"
                      i18n-values="title:autofill"></label>
             </div>
             <!-- Bookmarks -->
             <div class="sync-item-show" id="bookmarksItem">
               <input id="bookmarksCheckbox" name="dataTypeCheckbox" type="checkbox">
-              <label id="bookmarksCheckboxLabel" name="dataTypeLabel" 
+              <label id="bookmarksCheckboxLabel" name="dataTypeLabel"
                      for="bookmarksCheckbox" i18n-content="bookmarks"
                      i18n-values="title:bookmarks"></label>
             </div>
             <!-- Extensions -->
             <div class="sync-item-show" id="extensionsItem">
               <input id="extensionsCheckbox" name="dataTypeCheckbox" type="checkbox">
-              <label id="extensionsCheckboxLabel" name="dataTypeLabel" 
+              <label id="extensionsCheckboxLabel" name="dataTypeLabel"
                      for="extensionsCheckbox" i18n-content="extensions"
                      i18n-values="title:extensions"></label>
             </div>
             <!-- Omnibox -->
             <div class="sync-item-show" id="omniboxItem">
               <input id="typedUrlsCheckbox" name="dataTypeCheckbox" type="checkbox">
-              <label id="typedUrlsCheckboxLabel" name="dataTypeLabel" 
+              <label id="typedUrlsCheckboxLabel" name="dataTypeLabel"
                      for="typedUrlsCheckbox" i18n-content="typedurls"
                      i18n-values="title:typedurls"></label>
             </div>
             <!-- Passwords -->
             <div class="sync-item-show" id="passwordsItem">
               <input id="passwordsCheckbox" name="dataTypeCheckbox" type="checkbox">
-              <label id="passwordsCheckboxLabel" name="dataTypeLabel" 
+              <label id="passwordsCheckboxLabel" name="dataTypeLabel"
                      for="passwordsCheckbox" i18n-content="passwords"
                      i18n-values="title:passwords"></label>
             </div>
             <!-- Preferences -->
             <div class="sync-item-show" id="preferencesItem">
               <input id="preferencesCheckbox" name="dataTypeCheckbox" type="checkbox">
-              <label id="preferencesCheckboxLabel" name="dataTypeLabel" 
+              <label id="preferencesCheckboxLabel" name="dataTypeLabel"
                      for="preferencesCheckbox" i18n-content="preferences"
                      i18n-values="title:preferences"></label>
             </div>
@@ -458,7 +546,7 @@ html[os='mac'] input[type='submit'] {
             <!-- Sessions -->
             <div class="sync-item-show" id="sessionsItem">
               <input id="sessionsCheckbox" name="dataTypeCheckbox" type="checkbox">
-              <label id="sessionsCheckboxLabel" name="dataTypeLabel" 
+              <label id="sessionsCheckboxLabel" name="dataTypeLabel"
                      for="sessionsCheckbox" i18n-content="foreignsessions"
                      il8n-values="title:sessions"></label>
             </div>
@@ -475,21 +563,58 @@ html[os='mac'] input[type='submit'] {
 
   </div>
   <div id="encryption-tab-contents" class="sync-config-tab-contents-inactive">
-    <div id="sync-encryption-instructions" 
+    <div id="sync-encryption-instructions"
          i18n-content="encryptionInstructions"></div>
-    
-    <div class="sync-item-show" id="usePassphrase">
-      <input id="usePassphraseCheckbox" name="usePassphraseCheckbox"
-             type="checkbox" />
-      <label id="usePassphraseLabel" name="usePassphraseLabel"
-             for="usePassphraseCheckbox" i18n-content="usePassphraseLabel">
-      </label>
+
+    <div>
+      <input id="google-option" name="option" type="radio"
+             value="google" onchange="onRadioChange();">
+      <span i18n-content="googleOption"></span>
+    </input>
+    </div>
+    <div>
+      <input id="explicit-option" name="option" type="radio"
+             value="explicit" onchange="onRadioChange();">
+      <span i18n-content="explicitOption"></span>
+    </input>
+    </div>
+
+    <div class="sync-section" id="section-google">
+      <div i18n-content="sectionGoogleMessage"></div>
+    </div>
+    <div class="sync-section" id="section-explicit">
+      <div i18n-content="sectionExplicitMessage" id="explicit-message"></div>
+      <div>
+        <div i18n-content="passphraseLabel" id="passphraseLabel"></div>
+        <input id="passphrase" name="passphrase" label="passphraseLabel"
+               type="password" onkeyup="checkPassphraseMatch();"
+               onchange="checkPassphraseMatch();"/>
+      </div>
+      <div>
+        <div i18n-content="confirmLabel" id="confirmPassphraseLabel">
+        </div>
+        <input id="confirmpassphrase" name="confirmpassphrase" type="password"
+               label="confirmPassphraseLabel"
+               onkeyup="checkPassphraseMatch();"
+               onchange="checkPassphraseMatch();" />
+      </div>
+      <div class="error" style="display:none"
+           id="emptyerror" i18n-content="emptyErrorMessage"></div>
+      <div class="error" style="display:none"
+           id="mismatcherror" i18n-content="mismatchErrorMessage"></div>
     </div>
-    
-    <div id="sync-passphrase-warning" i18n-content="passphraseWarning">
+
+    <div id="change-passphrase">
+      <div id="sync-passphrase-warning" i18n-content="passphraseWarning">
+      </div>
+      <div id="sync-reset-confirmation" i18n-content="cleardataconfirmation"
+           style="display: none;">
+      </div>
+      <a id="clear-data-link" i18n-content="cleardatalink" href="#"
+             onclick='goToDashboard(); return false;'></a>
     </div>
   </div>
-  
+
   <div class="sync-footer">
     <input id="okButton" type="submit" i18n-values="value:ok" />
     <input id="cancelButton" type="button" i18n-values="value:cancel"
diff --git a/chrome/browser/sync/resources/encryption_login.html b/chrome/browser/sync/resources/encryption_login.html
new file mode 100644
index 0000000..7883cca
--- /dev/null
+++ b/chrome/browser/sync/resources/encryption_login.html
@@ -0,0 +1,6 @@
+<!-- This is intentionally an HTML fragment to be embedded
+     in the browser sign in HTML -->
+<div id="login_message">
+<h1>$1</h1>
+<p>$2</p>
+</div>
diff --git a/chrome/browser/sync/resources/firstpassphrase.html b/chrome/browser/sync/resources/firstpassphrase.html
new file mode 100644
index 0000000..4f82ef9
--- /dev/null
+++ b/chrome/browser/sync/resources/firstpassphrase.html
@@ -0,0 +1,204 @@
+<html i18n-values="dir:textdirection;">
+<head>
+<title></title>
+<style type="text/css">
+body {
+   line-height: 1.5em;
+   background: #FFFFFF;
+   font-size: 11pt;
+}
+html[os='mac'] body {
+  line-height: 1.5em;
+  background: #FFFFFF;
+}
+form {
+  -webkit-user-select: none;
+}
+.error {
+  color: red;
+  font-size: 10pt;
+ }
+.sync-header {
+  font-size: 1.2em;
+  font-weight: bold;
+  margin-bottom: 10px;
+}
+.sync-instructions {
+  margin-top: 10px;
+  margin-bottom: 10px;
+}
+.sync-footer {
+  position: fixed;
+  right: 0px;
+  bottom: 0px;
+  margin-right: 10px;
+  margin-bottom: 10px;
+}
+.sync-section {
+  background: #EEE;
+  margin: 5px;
+  padding: 10px;
+}
+html[dir='rtl'] .sync-footer {
+  text-align: left;
+  left: 0px;
+  bottom: 0px;
+  margin-left: 20px;
+}
+input[type='button'],
+input[type='submit'] {
+  min-width: 87px;
+  min-height: 26px;
+}
+html[os='mac'] input[type='button'],
+html[os='mac'] input[type='submit'] {
+  font-size: 12pt;
+}
+
+#passphrase {
+  margin-top: 5px;
+}
+
+#passphraseLabel,
+#confirmPassphraseLabel {
+  width: 145px;
+  float: left;
+  text-align: right;
+  margin-right: 4px;
+  padding-top: 3px;
+}
+
+</style>
+<script src="chrome://resources/js/cr.js"></script>
+<script>
+  var currentMode;
+
+  // Called once, when this html/js is loaded.
+  function setupDialog(args) {
+    // Allow platform specific rules
+    if (cr.isMac) {
+      document.documentElement.setAttribute('os', 'mac');
+    } else if (!cr.isWindows) {
+      document.documentElement.setAttribute('os', 'linux');
+    }
+
+    switchToMode("");
+  }
+
+  function switchToMode(mode) {
+    document.getElementById("section-explicit").style.display = "none";
+    document.getElementById("section-nothanks").style.display = "none";
+    document.getElementById("section-google").style.display = "none";
+
+    if (mode == "google") {
+      document.getElementById("section-google").style.display = "block";
+    } else if (mode =="explicit") {
+      document.getElementById("section-explicit").style.display = "block";
+    } else if (mode == "nothanks") {
+      document.getElementById("section-nothanks").style.display = "block";
+    }
+  }
+
+  function getRadioCheckedValue() {
+    var f = document.getElementById("form");
+    for (var i = 0; i < f.option.length; ++i) {
+      if (f.option[i].checked) {
+        return f.option[i].value;
+      }
+    }
+    return undefined;
+  }
+
+  function onRadioChange() {
+    switchToMode(getRadioCheckedValue());
+  }
+
+  function checkPassphraseMatch() {
+    var emptyError = document.getElementById("emptyerror");
+    var mismatchError = document.getElementById("mismatcherror");
+    emptyError.style.display = "none";
+    mismatchError.style.display = "none";
+
+    if (getRadioCheckedValue() != "explicit") {
+      return true;
+    }
+    var f = document.getElementById("form");
+    if (f.passphrase.value.length == 0) {
+      emptyError.style.display = "block";
+      return false;
+    }
+    if (f.confirmpassphrase.value.length > 0 &&
+        f.confirmpassphrase.value != f.passphrase.value) {
+      mismatchError.style.display = "block";
+      return false;
+    }
+    return true;
+  }
+
+  function sendValuesAndClose() {
+    var f = document.getElementById("form");
+    if (!checkPassphraseMatch()) {
+      return false;
+    }
+
+    var result = JSON.stringify({"option": getRadioCheckedValue(),
+                                 "passphrase": f.passphrase.value});
+    chrome.send("FirstPassphrase", [result]);
+  }
+</script>
+</head>
+<body i18n-values=".style.fontFamily:fontfamily" onload="setupDialog();">
+<form id="form" onSubmit="sendValuesAndClose(); return false;">
+  <div class="sync-header" id="title" i18n-content="title"></div>
+  <div class="sync-instructions" id="instructions"
+       i18n-content="instructions"></div>
+  <div>
+    <input name="option" type="radio" value="google" onchange="onRadioChange();">
+      <span i18n-content="googleOption"></span>
+    </input>
+  </div>
+  <div>
+    <input name="option" type="radio" value="explicit" onchange="onRadioChange();">
+    <span i18n-content="explicitOption"></span>
+    </input>
+  </div>
+  <div>
+    <input name="option" type="radio" value="nothanks" onchange="onRadioChange();">
+    <span i18n-content="nothanksOption"></span>
+    </input>
+  </div>
+
+  <div class="sync-section" id="section-google">
+    <div i18n-content="sectionGoogleMessage"></div>
+  </div>
+  <div class="sync-section" id="section-explicit">
+    <div i18n-content="sectionExplicitMessage"></div>
+    <div>
+      <div i18n-content="passphraseLabel" id="passphraseLabel"></div>
+      <input id="passphrase" name="passphrase" label="passphraseLabel"
+             type="password" onkeyup="checkPassphraseMatch();"
+             onchange="checkPassphraseMatch();"/>
+    </div>
+    <div>
+      <div i18n-content="confirmLabel" id="confirmPassphraseLabel">
+      </div>
+      <input id="confirmpassphrase" name="confirmpassphrase" type="password"
+             label="confirmPassphraseLabel"
+             onkeyup="checkPassphraseMatch();"
+             onchange="checkPassphraseMatch();" />
+    </div>
+    <div class="error" style="display:none"
+         id="emptyerror" i18n-content="emptyErrorMessage"></div>
+    <div class="error" style="display:none"
+         id="mismatcherror" i18n-content="mismatchErrorMessage"></div>
+  </div>
+  <div class="sync-section" id="section-nothanks">
+    <div i18n-content="sectionNothanksMessage"></div>
+  </div>
+
+  <div class="sync-footer">
+    <input id="okButton" type="submit" i18n-values="value:ok" />
+  </div>
+</form>
+</body>
+</html>
diff --git a/chrome/browser/sync/resources/setup_flow.html b/chrome/browser/sync/resources/setup_flow.html
index a3de363..495828f 100644
--- a/chrome/browser/sync/resources/setup_flow.html
+++ b/chrome/browser/sync/resources/setup_flow.html
@@ -3,7 +3,8 @@
 <title></title>
 <script type="text/javascript">
   function hideAllPages() {
-    var pages = ['login', 'configure', 'passphrase', 'settingup', 'done'];
+    var pages = ['login', 'configure', 'passphrase',
+                 'settingup', 'done', 'firstpassphrase'];
     for (var i = 0; i < pages.length; ++i) {
       document.getElementById(pages[i]).style.display = 'none';
       document.getElementById(pages[i]).tabIndex = -1;
@@ -21,6 +22,7 @@
   function showPassphrase() { showPage('passphrase'); }
   function showSettingUp() { showPage('settingup'); }
   function showSetupDone() { showPage('done'); }
+  function showFirstPassphrase() { showPage('firstpassphrase'); }
 
   // Called once, when this html/js is loaded.
   function showTheRightIframe() {
@@ -45,5 +47,8 @@
   <iframe id="done" frameborder="0" width="100%" scrolling="no" height="100%"
           src="chrome://syncresources/setupdone" style="display:none"
           tabindex="-1"></iframe>
+  <iframe id="firstpassphrase" frameborder="0" width="100%" scrolling="no"
+          height="100%" src="chrome://syncresources/firstpassphrase"
+          style="display:none" tabindex="-1"></iframe>
 </body>
 </html>
diff --git a/chrome/browser/sync/sync_setup_flow.cc b/chrome/browser/sync/sync_setup_flow.cc
index a6dd5ec..adb06ea 100644
--- a/chrome/browser/sync/sync_setup_flow.cc
+++ b/chrome/browser/sync/sync_setup_flow.cc
@@ -44,6 +44,10 @@ void FlowHandler::RegisterMessages() {
       NewCallback(this, &FlowHandler::HandleConfigure));
   dom_ui_->RegisterMessageCallback("Passphrase",
       NewCallback(this, &FlowHandler::HandlePassphraseEntry));
+  dom_ui_->RegisterMessageCallback("FirstPassphrase",
+      NewCallback(this, &FlowHandler::HandleFirstPassphrase));
+  dom_ui_->RegisterMessageCallback("GoToDashboard",
+      NewCallback(this, &FlowHandler::HandleGoToDashboard));
 }
 
 static bool GetAuthData(const std::string& json,
@@ -76,6 +80,18 @@ bool GetPassphrase(const std::string& json, std::string* passphrase,
          result->GetString("mode", mode);
 }
 
+bool GetFirstPassphrase(const std::string& json,
+                        std::string* option,
+                        std::string* passphrase) {
+  scoped_ptr<Value> parsed_value(base::JSONReader::Read(json, false));
+  if (!parsed_value.get() || !parsed_value->IsType(Value::TYPE_DICTIONARY))
+    return false;
+
+  DictionaryValue* result = static_cast<DictionaryValue*>(parsed_value.get());
+  return result->GetString("option", option) &&
+         result->GetString("passphrase", passphrase);
+}
+
 static bool GetConfiguration(const std::string& json,
                              SyncConfiguration* config) {
   scoped_ptr<Value> parsed_value(base::JSONReader::Read(json, false));
@@ -145,6 +161,9 @@ static bool GetConfiguration(const std::string& json,
   // Encyption settings.
   if (!result->GetBoolean("usePassphrase", &config->use_secondary_passphrase))
     return false;
+  if (config->use_secondary_passphrase &&
+      !result->GetString("passphrase", &config->secondary_passphrase))
+    return false;
 
   return true;
 }
@@ -204,6 +223,28 @@ void FlowHandler::HandlePassphraseEntry(const ListValue* args) {
   flow_->OnPassphraseEntry(passphrase, mode);
 }
 
+void FlowHandler::HandleFirstPassphrase(const ListValue* args) {
+  std::string json(dom_ui_util::GetJsonResponseFromFirstArgumentInList(args));
+
+  if (json.empty())
+    return;
+
+  std::string option;
+  std::string passphrase;
+  if (!GetFirstPassphrase(json, &option, &passphrase)) {
+    // Page sent result which couldn't be parsed.  Programming error.
+    NOTREACHED();
+    return;
+  }
+
+  DCHECK(flow_);
+  flow_->OnFirstPassphraseEntry(option, passphrase);
+}
+
+void FlowHandler::HandleGoToDashboard(const ListValue* args) {
+  flow_->OnGoToDashboard();
+}
+
 // Called by SyncSetupFlow::Advance.
 void FlowHandler::ShowGaiaLogin(const DictionaryValue& args) {
   // Whenever you start a wizard, you pass in an arg so it starts on the right
@@ -258,6 +299,17 @@ void FlowHandler::ShowPassphraseEntry(const DictionaryValue& args) {
   ExecuteJavascriptInIFrame(kPassphraseIFrameXPath, script);
 }
 
+void FlowHandler::ShowFirstPassphrase(const DictionaryValue& args) {
+  if (dom_ui_)
+    dom_ui_->CallJavascriptFunction(L"showFirstPassphrase");
+
+  std::string json;
+  base::JSONWriter::Write(&args, false, &json);
+  std::wstring script = std::wstring(L"setupDialog") +
+      L"(" + UTF8ToWide(json) + L");";
+  ExecuteJavascriptInIFrame(kPassphraseIFrameXPath, script);
+}
+
 void FlowHandler::ShowSettingUp() {
   if (dom_ui_)
     dom_ui_->CallJavascriptFunction(L"showSettingUp");
@@ -306,7 +358,6 @@ SyncSetupFlow::SyncSetupFlow(SyncSetupWizard::State start_state,
       login_start_time_(base::TimeTicks::Now()),
       flow_handler_(new FlowHandler()),
       owns_flow_handler_(true),
-      configuration_pending_(false),
       service_(service),
       html_dialog_window_(NULL) {
   flow_handler_->set_flow(this);
@@ -390,7 +441,8 @@ void SyncSetupFlow::OnDialogClosed(const std::string& json_retval) {
 }
 
 std::wstring SyncSetupFlow::GetDialogTitle() const {
-  return l10n_util::GetString(IDS_SYNC_MY_BOOKMARKS_LABEL);
+  return UTF16ToWideHack(
+      l10n_util::GetStringUTF16(IDS_SYNC_MY_BOOKMARKS_LABEL));
 }
 
 bool SyncSetupFlow::IsDialogModal() const {
@@ -502,8 +554,6 @@ bool SyncSetupFlow::ShouldAdvance(SyncSetupWizard::State state) {
       return current_state_ == SyncSetupWizard::GAIA_LOGIN;
     case SyncSetupWizard::CONFIGURE:
       return current_state_ == SyncSetupWizard::GAIA_SUCCESS;
-    case SyncSetupWizard::CREATE_PASSPHRASE:
-      return current_state_ == SyncSetupWizard::CONFIGURE;
     case SyncSetupWizard::ENTER_PASSPHRASE:
       return current_state_ == SyncSetupWizard::CONFIGURE ||
              current_state_ == SyncSetupWizard::SETTING_UP;
@@ -511,8 +561,8 @@ bool SyncSetupFlow::ShouldAdvance(SyncSetupWizard::State state) {
       return current_state_ == SyncSetupWizard::CONFIGURE;
     case SyncSetupWizard::SETTING_UP:
       return current_state_ == SyncSetupWizard::CONFIGURE ||
-             current_state_ == SyncSetupWizard::CREATE_PASSPHRASE ||
-             current_state_ == SyncSetupWizard::ENTER_PASSPHRASE;
+             current_state_ == SyncSetupWizard::ENTER_PASSPHRASE ||
+             current_state_ == SyncSetupWizard::PASSPHRASE_MIGRATION;
     case SyncSetupWizard::FATAL_ERROR:
       return true;  // You can always hit the panic button.
     case SyncSetupWizard::DONE_FIRST_TIME:
@@ -553,16 +603,16 @@ void SyncSetupFlow::Advance(SyncSetupWizard::State advance_state) {
       flow_handler_->ShowConfigure(args);
       break;
     }
-    case SyncSetupWizard::CREATE_PASSPHRASE: {
+    case SyncSetupWizard::ENTER_PASSPHRASE: {
       DictionaryValue args;
-      args.SetString("mode", "new");
+      SyncSetupFlow::GetArgsForEnterPassphrase(service_, &args);
       flow_handler_->ShowPassphraseEntry(args);
       break;
     }
-    case SyncSetupWizard::ENTER_PASSPHRASE: {
+    case SyncSetupWizard::PASSPHRASE_MIGRATION: {
       DictionaryValue args;
-      SyncSetupFlow::GetArgsForEnterPassphrase(service_, &args);
-      flow_handler_->ShowPassphraseEntry(args);
+      args.SetString("iframeToShow", "firstpassphrase");
+      flow_handler_->ShowFirstPassphrase(args);
       break;
     }
     case SyncSetupWizard::SETUP_ABORTED_BY_PENDING_CLEAR: {
@@ -629,6 +679,9 @@ SyncSetupFlow* SyncSetupFlow::Run(ProfileSyncService* service,
     SyncSetupFlow::GetArgsForConfigure(service, &args);
   else if (start == SyncSetupWizard::ENTER_PASSPHRASE)
     SyncSetupFlow::GetArgsForEnterPassphrase(service, &args);
+  else if (start == SyncSetupWizard::PASSPHRASE_MIGRATION)
+    args.SetString("iframeToShow", "firstpassphrase");
+
   std::string json_args;
   base::JSONWriter::Write(&args, false, &json_args);
 
@@ -663,56 +716,47 @@ void SyncSetupFlow::OnUserSubmittedAuth(const std::string& username,
 }
 
 void SyncSetupFlow::OnUserConfigured(const SyncConfiguration& configuration) {
-  // Store the configuration in case we need more information.
-  configuration_ = configuration;
-  configuration_pending_ = true;
-
-  // If the user is activating secondary passphrase for the first time,
-  // we need to prompt them to enter one.
-  if (configuration.use_secondary_passphrase &&
-      !service_->IsUsingSecondaryPassphrase()) {
-    // TODO(tim): If we could download the Nigori node first before any other
-    // types, we could do that prior to showing the configure page so that we
-    // could pre-populate the 'Use an encryption passphrase' checkbox.
-    // http://crbug.com/60182
-    Advance(SyncSetupWizard::CREATE_PASSPHRASE);
-    return;
-  }
-
-  OnConfigurationComplete();
-}
-
-void SyncSetupFlow::OnConfigurationComplete() {
-  if (!configuration_pending_)
-    return;
-
   // Go to the "loading..." screen."
   Advance(SyncSetupWizard::SETTING_UP);
 
   // If we are activating the passphrase, we need to have one supplied.
   DCHECK(service_->IsUsingSecondaryPassphrase() ||
-         !configuration_.use_secondary_passphrase ||
-         configuration_.secondary_passphrase.length() > 0);
+         !configuration.use_secondary_passphrase ||
+         configuration.secondary_passphrase.length() > 0);
 
-  if (configuration_.use_secondary_passphrase &&
+  if (configuration.use_secondary_passphrase &&
       !service_->IsUsingSecondaryPassphrase()) {
-    service_->SetPassphrase(configuration_.secondary_passphrase, true);
+    service_->SetPassphrase(configuration.secondary_passphrase, true);
   }
 
-  service_->OnUserChoseDatatypes(configuration_.sync_everything,
-                                 configuration_.data_types);
-
-  configuration_pending_ = false;
+  service_->OnUserChoseDatatypes(configuration.sync_everything,
+                                 configuration.data_types);
 }
 
 void SyncSetupFlow::OnPassphraseEntry(const std::string& passphrase,
                                       const std::string& mode) {
-  if (current_state_ == SyncSetupWizard::ENTER_PASSPHRASE) {
-    service_->SetPassphrase(passphrase, mode == std::string("enter"));
-    Advance(SyncSetupWizard::SETTING_UP);
-  } else if (configuration_pending_) {
-    DCHECK_EQ(SyncSetupWizard::CREATE_PASSPHRASE, current_state_);
-    configuration_.secondary_passphrase = passphrase;
-    OnConfigurationComplete();
+  Advance(SyncSetupWizard::SETTING_UP);
+  service_->SetPassphrase(passphrase, true);
+}
+
+void SyncSetupFlow::OnFirstPassphraseEntry(const std::string& option,
+                                           const std::string& passphrase) {
+  Advance(SyncSetupWizard::SETTING_UP);
+  if (option == "explicit") {
+    service_->SetPassphrase(passphrase, true);
+  } else if (option == "nothanks") {
+    // User opted out of encrypted sync, need to turn off encrypted
+    // data types.
+    syncable::ModelTypeSet registered_types;
+    service_->GetRegisteredDataTypes(&registered_types);
+    registered_types.erase(syncable::PASSWORDS);
+    service_->OnUserChoseDatatypes(false, registered_types);
+  } else if (option == "google") {
+    // Implicit passphrase already set up.
+    Advance(SyncSetupWizard::DONE);
   }
 }
+
+void SyncSetupFlow::OnGoToDashboard() {
+  BrowserList::GetLastActive()->OpenPrivacyDashboardTabAndActivate();
+}
diff --git a/chrome/browser/sync/sync_setup_flow.h b/chrome/browser/sync/sync_setup_flow.h
index 8bfc443..f6c0233 100644
--- a/chrome/browser/sync/sync_setup_flow.h
+++ b/chrome/browser/sync/sync_setup_flow.h
@@ -110,7 +110,10 @@ class SyncSetupFlow : public HtmlDialogUIDelegate {
   void OnPassphraseEntry(const std::string& passphrase,
                          const std::string& mode);
 
-  void OnConfigurationComplete();
+  void OnFirstPassphraseEntry(const std::string& option,
+                              const std::string& passphrase);
+
+  void OnGoToDashboard();
 
  private:
   FRIEND_TEST_ALL_PREFIXES(SyncSetupWizardTest, InitialStepLogin);
@@ -124,6 +127,7 @@ class SyncSetupFlow : public HtmlDialogUIDelegate {
   FRIEND_TEST_ALL_PREFIXES(SyncSetupWizardTest,
                            DiscreteRunChooseDataTypesAbortedByPendingClear);
   FRIEND_TEST_ALL_PREFIXES(SyncSetupWizardTest, EnterPassphraseRequired);
+  FRIEND_TEST_ALL_PREFIXES(SyncSetupWizardTest, PassphraseMigration);
 
   // Use static Run method to get an instance.
   SyncSetupFlow(SyncSetupWizard::State start_state,
@@ -149,11 +153,6 @@ class SyncSetupFlow : public HtmlDialogUIDelegate {
   FlowHandler* flow_handler_;
   mutable bool owns_flow_handler_;
 
-  // The current configuration, held pending until all the information has
-  // been populated (possibly using multiple dialog states).
-  SyncConfiguration configuration_;
-  bool configuration_pending_;
-
   // We need this to write the sentinel "setup completed" pref.
   ProfileSyncService* service_;
 
@@ -198,6 +197,8 @@ class FlowHandler : public DOMMessageHandler {
   void HandleSubmitAuth(const ListValue* args);
   void HandleConfigure(const ListValue* args);
   void HandlePassphraseEntry(const ListValue* args);
+  void HandleFirstPassphrase(const ListValue* args);
+  void HandleGoToDashboard(const ListValue* args);
 
   // These functions control which part of the HTML is visible.
   void ShowGaiaLogin(const DictionaryValue& args);
@@ -205,6 +206,7 @@ class FlowHandler : public DOMMessageHandler {
   void ShowGaiaSuccessAndSettingUp();
   void ShowConfigure(const DictionaryValue& args);
   void ShowPassphraseEntry(const DictionaryValue& args);
+  void ShowFirstPassphrase(const DictionaryValue& args);
   void ShowSettingUp();
   void ShowSetupDone(const std::wstring& user);
   void ShowFirstTimeDone(const std::wstring& user);
diff --git a/chrome/browser/sync/sync_setup_wizard.cc b/chrome/browser/sync/sync_setup_wizard.cc
index e80afe0..6e9d254 100644
--- a/chrome/browser/sync/sync_setup_wizard.cc
+++ b/chrome/browser/sync/sync_setup_wizard.cc
@@ -79,6 +79,7 @@ void SyncResourcesSource::StartDataRequest(const std::string& path_raw,
   const char kSyncGaiaLoginPath[] = "gaialogin";
   const char kSyncConfigurePath[] = "configure";
   const char kSyncPassphrasePath[] = "passphrase";
+  const char kSyncFirstPassphrasePath[] = "firstpassphrase";
   const char kSyncSettingUpPath[] = "settingup";
   const char kSyncSetupDonePath[] = "setupdone";
 
@@ -149,23 +150,48 @@ void SyncResourcesSource::StartDataRequest(const std::string& path_raw,
         GetStringFUTF16(IDS_SYNC_ENCRYPTION_INSTRUCTIONS,
                         GetStringUTF16(IDS_PRODUCT_NAME)));
     AddString(dict, "encryptAllLabel", IDS_SYNC_ENCRYPT_ALL_LABEL);
-    AddString(dict, "usePassphraseLabel", IDS_SYNC_PASSPHRASE_CHECKBOX_LABEL);
+
+    AddString(dict, "googleOption", IDS_SYNC_PASSPHRASE_OPT_GOOGLE);
+    AddString(dict, "explicitOption", IDS_SYNC_PASSPHRASE_OPT_EXPLICIT);
+    AddString(dict, "sectionGoogleMessage", IDS_SYNC_PASSPHRASE_MSG_GOOGLE);
+    AddString(dict, "sectionExplicitMessage", IDS_SYNC_PASSPHRASE_MSG_EXPLICIT);
+    AddString(dict, "passphraseLabel", IDS_SYNC_PASSPHRASE_LABEL);
+    AddString(dict, "confirmLabel", IDS_SYNC_CONFIRM_PASSPHRASE_LABEL);
+    AddString(dict, "emptyErrorMessage", IDS_SYNC_EMPTY_PASSPHRASE_ERROR);
+    AddString(dict, "mismatchErrorMessage", IDS_SYNC_PASSPHRASE_MISMATCH_ERROR);
+
     AddString(dict, "passphraseWarning", IDS_SYNC_PASSPHRASE_WARNING);
+    AddString(dict, "cleardata", IDS_SYNC_CLEAR_DATA_FOR_PASSPHRASE);
+    AddString(dict, "cleardatalink", IDS_SYNC_CLEAR_DATA_LINK);
 
     // Stuff for the footer.
     AddString(dict, "ok", IDS_OK);
     AddString(dict, "cancel", IDS_CANCEL);
   } else if (path_raw == kSyncPassphrasePath) {
     html_resource_id = IDR_SYNC_PASSPHRASE_HTML;
-    AddString(dict, "newPassphraseTitle", IDS_SYNC_NEW_PASSPHRASE_TITLE);
-    AddString(dict, "newPassphraseBody", IDS_SYNC_NEW_PASSPHRASE_BODY);
     AddString(dict, "enterPassphraseTitle", IDS_SYNC_ENTER_PASSPHRASE_TITLE);
     AddString(dict, "enterPassphraseBody", IDS_SYNC_ENTER_PASSPHRASE_BODY);
-    AddString(dict, "gaiaPassphraseTitle", IDS_SYNC_GAIA_PASSPHRASE_TITLE);
-    AddString(dict, "gaiaPassphraseBody", IDS_SYNC_GAIA_PASSPHRASE_BODY);
     AddString(dict, "passphraseLabel", IDS_SYNC_PASSPHRASE_LABEL);
     AddString(dict, "ok", IDS_OK);
     AddString(dict, "cancel", IDS_CANCEL);
+  } else if (path_raw == kSyncFirstPassphrasePath) {
+    html_resource_id = IDR_SYNC_FIRST_PASSPHRASE_HTML;
+    AddString(dict, "title", IDS_SYNC_FIRST_PASSPHRASE_TITLE);
+    dict->SetString("instructions",
+                    GetStringFUTF16(IDS_SYNC_FIRST_PASSPHRASE_MESSAGE,
+                                    GetStringUTF16(IDS_PRODUCT_NAME)));
+    AddString(dict, "googleOption", IDS_SYNC_PASSPHRASE_OPT_GOOGLE);
+    AddString(dict, "explicitOption", IDS_SYNC_PASSPHRASE_OPT_EXPLICIT);
+    AddString(dict, "nothanksOption", IDS_SYNC_PASSPHRASE_OPT_CANCEL);
+    AddString(dict, "sectionGoogleMessage", IDS_SYNC_PASSPHRASE_MSG_GOOGLE);
+    AddString(dict, "sectionExplicitMessage", IDS_SYNC_PASSPHRASE_MSG_EXPLICIT);
+    AddString(dict, "sectionNothanksMessage", IDS_SYNC_PASSPHRASE_MSG_CANCEL);
+    AddString(dict, "passphraseLabel", IDS_SYNC_PASSPHRASE_LABEL);
+    AddString(dict, "confirmLabel", IDS_SYNC_CONFIRM_PASSPHRASE_LABEL);
+    AddString(dict, "emptyErrorMessage", IDS_SYNC_EMPTY_PASSPHRASE_ERROR);
+    AddString(dict, "mismatchErrorMessage", IDS_SYNC_PASSPHRASE_MISMATCH_ERROR);
+    AddString(dict, "ok", IDS_OK);
+    AddString(dict, "cancel", IDS_CANCEL);
   } else if (path_raw == kSyncSettingUpPath) {
     html_resource_id = IDR_SYNC_SETTING_UP_HTML;
 
@@ -279,9 +305,9 @@ SyncSetupWizard::State SyncSetupWizard::GetEndStateForDiscreteRun(
   State result = FATAL_ERROR;
   if (start_state == GAIA_LOGIN) {
     result = GAIA_SUCCESS;
-  } else if (start_state == ENTER_PASSPHRASE) {
-    result = DONE;
-  } else if (start_state == CONFIGURE) {
+  } else if (start_state == ENTER_PASSPHRASE ||
+             start_state == CONFIGURE ||
+             start_state == PASSPHRASE_MIGRATION) {
     result = DONE;
   }
   DCHECK_NE(FATAL_ERROR, result) <<
diff --git a/chrome/browser/sync/sync_setup_wizard.h b/chrome/browser/sync/sync_setup_wizard.h
index dad3fa9..76b6fae 100644
--- a/chrome/browser/sync/sync_setup_wizard.h
+++ b/chrome/browser/sync/sync_setup_wizard.h
@@ -29,10 +29,11 @@ class SyncSetupWizard {
     //  Encryption --
     //   Choose what to encrypt and whether to use a passphrase.
     CONFIGURE,
-    // Show the screen that lets you enter a new passphrase
-    CREATE_PASSPHRASE,
     // Show the screen that prompts for your passphrase
     ENTER_PASSPHRASE,
+    // Show the passphrase "first time" screen for migrating users, where all
+    // is explained and they choose between google password/custom passphrase.
+    PASSPHRASE_MIGRATION,
     // The panic switch.  Something went terribly wrong during setup and we
     // can't recover.
     FATAL_ERROR,
diff --git a/chrome/browser/sync/sync_setup_wizard_unittest.cc b/chrome/browser/sync/sync_setup_wizard_unittest.cc
index 46a0d69..b0da0d7 100644
--- a/chrome/browser/sync/sync_setup_wizard_unittest.cc
+++ b/chrome/browser/sync/sync_setup_wizard_unittest.cc
@@ -312,6 +312,7 @@ TEST_F(SyncSetupWizardTest, InitialStepLogin) {
 TEST_F(SyncSetupWizardTest, ChooseDataTypesSetsPrefs) {
   SKIP_TEST_ON_MACOSX();
   wizard_->Step(SyncSetupWizard::GAIA_LOGIN);
+  wizard_->Step(SyncSetupWizard::GAIA_SUCCESS);
   wizard_->Step(SyncSetupWizard::CONFIGURE);
 
   ListValue data_type_choices_value;
@@ -359,6 +360,22 @@ TEST_F(SyncSetupWizardTest, EnterPassphraseRequired) {
   EXPECT_EQ("myPassphrase", service_->passphrase_);
 }
 
+TEST_F(SyncSetupWizardTest, PassphraseMigration) {
+  SKIP_TEST_ON_MACOSX();
+  wizard_->Step(SyncSetupWizard::PASSPHRASE_MIGRATION);
+  ListValue value;
+  value.Append(new StringValue("{\"option\":\"explicit\","
+                               "\"passphrase\":\"myPassphrase\"}"));
+  test_window_->flow()->flow_handler_->HandleFirstPassphrase(&value);
+  EXPECT_EQ("myPassphrase", service_->passphrase_);
+
+  ListValue value2;
+  value2.Append(new StringValue("{\"option\":\"nothanks\","
+                                "\"passphrase\":\"myPassphrase\"}"));
+  test_window_->flow()->flow_handler_->HandleFirstPassphrase(&value2);
+  EXPECT_EQ(service_->chosen_data_types_.count(syncable::PASSWORDS), 0U);
+}
+
 TEST_F(SyncSetupWizardTest, DialogCancelled) {
   SKIP_TEST_ON_MACOSX();
   wizard_->Step(SyncSetupWizard::GAIA_LOGIN);
diff --git a/chrome/browser/sync/sync_ui_util.cc b/chrome/browser/sync/sync_ui_util.cc
index 27fdb9a..d49ada1 100644
--- a/chrome/browser/sync/sync_ui_util.cc
+++ b/chrome/browser/sync/sync_ui_util.cc
@@ -5,6 +5,7 @@
 #include "chrome/browser/sync/sync_ui_util.h"
 
 #include "app/l10n_util.h"
+#include "app/resource_bundle.h"
 #include "base/i18n/number_formatting.h"
 #include "base/i18n/time_formatting.h"
 #include "base/string_util.h"
@@ -13,6 +14,7 @@
 #include "chrome/browser/sync/profile_sync_service.h"
 #include "chrome/browser/ui/options/options_window.h"
 #include "chrome/common/net/gaia/google_service_auth_error.h"
+#include "grit/browser_resources.h"
 #include "grit/chromium_strings.h"
 #include "grit/generated_resources.h"
 
@@ -102,8 +104,28 @@ MessageType GetStatusInfo(ProfileSyncService* service,
           l10n_util::GetStringUTF16(IDS_SYNC_AUTHENTICATING_LABEL));
       }
       result_type = PRE_SYNCED;
-    } else if (auth_error.state() != AuthError::NONE ||
-               service->observed_passphrase_required()) {
+    } else if (service->observed_passphrase_required()) {
+      if (service->passphrase_required_for_decryption()) {
+        // NOT first machine.
+        // Show a link and present as an error ("needs attention").
+        if (status_label && link_label) {
+          status_label->assign(string16());
+          link_label->assign(
+              l10n_util::GetStringUTF16(IDS_SYNC_CONFIGURE_ENCRYPTION));
+        }
+        result_type = SYNC_ERROR;
+      } else {
+        // First machine.  Show as a promotion.
+        if (status_label && link_label) {
+          status_label->assign(
+              l10n_util::GetStringFUTF16(IDS_SYNC_NTP_PASSWORD_PROMO,
+                  l10n_util::GetStringUTF16(IDS_PRODUCT_NAME)));
+          link_label->assign(
+              l10n_util::GetStringUTF16(IDS_SYNC_NTP_PASSWORD_ENABLE));
+        }
+        result_type = SYNC_PROMO;
+      }
+    } else if (auth_error.state() != AuthError::NONE) {
       if (status_label && link_label) {
         GetStatusLabelsForAuthError(auth_error, service,
                                     status_label, link_label);
@@ -156,6 +178,20 @@ MessageType GetStatusInfo(ProfileSyncService* service,
 
 }  // namespace
 
+// Returns an HTML chunk for a login prompt related to encryption.
+string16 GetLoginMessageForEncryption() {
+  std::vector<std::string> subst;
+  const base::StringPiece html(
+      ResourceBundle::GetSharedInstance().GetRawDataResource(
+          IDR_SYNC_ENCRYPTION_LOGIN_HTML));
+  subst.push_back(l10n_util::GetStringUTF8(IDS_SYNC_PLEASE_SIGN_IN));
+  subst.push_back(
+      l10n_util::GetStringFUTF8(IDS_SYNC_LOGIN_FOR_ENCRYPTION,
+                                l10n_util::GetStringUTF16(IDS_PRODUCT_NAME)));
+
+  return UTF8ToUTF16(ReplaceStringPlaceholders(html, subst, NULL));
+}
+
 MessageType GetStatusLabels(ProfileSyncService* service,
                             string16* status_label,
                             string16* link_label) {
@@ -322,6 +358,12 @@ void ConstructAboutInformation(ProfileSyncService* service,
       std::string location_str;
       loc.Write(true, true, &location_str);
       strings->SetString("unrecoverable_error_location", location_str);
+    } else if (!service->sync_initialized()) {
+      strings->SetString("summary", "Sync not yet initialized");
+    } else if (service->backend() == NULL) {
+      strings->SetString("summary",
+          "Unrecoverable error detected. Backend is null when it shouldnt be");
+      NOTREACHED();
     } else {
       browser_sync::ModelSafeRoutingInfo routes;
       service->backend()->GetModelSafeRoutingInfo(&routes);
diff --git a/chrome/browser/sync/sync_ui_util.h b/chrome/browser/sync/sync_ui_util.h
index 8bcd85a..5a168c4 100644
--- a/chrome/browser/sync/sync_ui_util.h
+++ b/chrome/browser/sync/sync_ui_util.h
@@ -24,11 +24,15 @@ enum MessageType {
   PRE_SYNCED,  // User has not set up sync.
   SYNCED,      // We are synced and authenticated to a gmail account.
   SYNC_ERROR,  // A sync error (such as invalid credentials) has occurred.
+  SYNC_PROMO,  // A situation has occurred which should be brought to the user's
+               // attention, but not as an error.
 };
 
 // TODO(akalin): audit the use of ProfileSyncService* service below,
 // and use const ProfileSyncService& service where possible.
 
+string16 GetLoginMessageForEncryption();
+
 // Create status and link labels for the current status labels and link text
 // by querying |service|.
 MessageType GetStatusLabels(ProfileSyncService* service,
@@ -60,4 +64,3 @@ void AddIntSyncDetail(ListValue* details,
                       int64 stat_value);
 }  // namespace sync_ui_util
 #endif  // CHROME_BROWSER_SYNC_SYNC_UI_UTIL_H_
-
diff --git a/chrome/browser/sync/syncable/syncable_unittest.cc b/chrome/browser/sync/syncable/syncable_unittest.cc
index 32a4cc3..6c887b2 100644
--- a/chrome/browser/sync/syncable/syncable_unittest.cc
+++ b/chrome/browser/sync/syncable/syncable_unittest.cc
@@ -23,10 +23,10 @@
 #include "base/file_path.h"
 #include "base/file_util.h"
 #include "base/logging.h"
-#include "base/platform_thread.h"
 #include "base/scoped_ptr.h"
 #include "base/scoped_temp_dir.h"
 #include "base/string_util.h"
+#include "base/threading/platform_thread.h"
 #include "chrome/browser/sync/engine/syncproto.h"
 #include "chrome/browser/sync/protocol/bookmark_specifics.pb.h"
 #include "chrome/browser/sync/syncable/directory_backing_store.h"
@@ -386,7 +386,7 @@ TEST_F(SyncableDirectoryTest, TakeSnapshotGetsMetahandlesToPurge) {
   dir_->PurgeEntriesWithTypeIn(to_purge);
 
   Directory::SaveChangesSnapshot snapshot1;
-  AutoLock scoped_lock(dir_->kernel_->save_changes_mutex);
+  base::AutoLock scoped_lock(dir_->kernel_->save_changes_mutex);
   dir_->TakeSnapshotForSaveChanges(&snapshot1);
   EXPECT_TRUE(expected_purges == snapshot1.metahandles_to_purge);
 
@@ -415,7 +415,7 @@ TEST_F(SyncableDirectoryTest, TakeSnapshotGetsAllDirtyHandlesTest) {
   // Fake SaveChanges() and make sure we got what we expected.
   {
     Directory::SaveChangesSnapshot snapshot;
-    AutoLock scoped_lock(dir_->kernel_->save_changes_mutex);
+    base::AutoLock scoped_lock(dir_->kernel_->save_changes_mutex);
     dir_->TakeSnapshotForSaveChanges(&snapshot);
     // Make sure there's an entry for each new metahandle.  Make sure all
     // entries are marked dirty.
@@ -448,7 +448,7 @@ TEST_F(SyncableDirectoryTest, TakeSnapshotGetsAllDirtyHandlesTest) {
   // Fake SaveChanges() and make sure we got what we expected.
   {
     Directory::SaveChangesSnapshot snapshot;
-    AutoLock scoped_lock(dir_->kernel_->save_changes_mutex);
+    base::AutoLock scoped_lock(dir_->kernel_->save_changes_mutex);
     dir_->TakeSnapshotForSaveChanges(&snapshot);
     // Make sure there's an entry for each new metahandle.  Make sure all
     // entries are marked dirty.
@@ -588,7 +588,7 @@ TEST_F(SyncableDirectoryTest, TakeSnapshotGetsOnlyDirtyHandlesTest) {
   // Fake SaveChanges() and make sure we got what we expected.
   {
     Directory::SaveChangesSnapshot snapshot;
-    AutoLock scoped_lock(dir_->kernel_->save_changes_mutex);
+    base::AutoLock scoped_lock(dir_->kernel_->save_changes_mutex);
     dir_->TakeSnapshotForSaveChanges(&snapshot);
     // Make sure there are no dirty_metahandles.
     EXPECT_EQ(0u, snapshot.dirty_metas.size());
@@ -614,7 +614,7 @@ TEST_F(SyncableDirectoryTest, TakeSnapshotGetsOnlyDirtyHandlesTest) {
   // Fake SaveChanges() and make sure we got what we expected.
   {
     Directory::SaveChangesSnapshot snapshot;
-    AutoLock scoped_lock(dir_->kernel_->save_changes_mutex);
+    base::AutoLock scoped_lock(dir_->kernel_->save_changes_mutex);
     dir_->TakeSnapshotForSaveChanges(&snapshot);
     // Make sure there's an entry for each changed metahandle.  Make sure all
     // entries are marked dirty.
@@ -1356,7 +1356,7 @@ TEST(SyncableDirectoryManager, TestFileRelease) {
   ASSERT_TRUE(file_util::Delete(dm.GetSyncDataDatabasePath(), true));
 }
 
-class ThreadOpenTestDelegate : public PlatformThread::Delegate {
+class ThreadOpenTestDelegate : public base::PlatformThread::Delegate {
  public:
   explicit ThreadOpenTestDelegate(DirectoryManager* dm)
       : directory_manager_(dm) {}
@@ -1373,10 +1373,10 @@ class ThreadOpenTestDelegate : public PlatformThread::Delegate {
 
 TEST(SyncableDirectoryManager, ThreadOpenTest) {
   DirectoryManager dm(FilePath(FILE_PATH_LITERAL(".")));
-  PlatformThreadHandle thread_handle;
+  base::PlatformThreadHandle thread_handle;
   ThreadOpenTestDelegate test_delegate(&dm);
-  ASSERT_TRUE(PlatformThread::Create(0, &test_delegate, &thread_handle));
-  PlatformThread::Join(thread_handle);
+  ASSERT_TRUE(base::PlatformThread::Create(0, &test_delegate, &thread_handle));
+  base::PlatformThread::Join(thread_handle);
   {
     ScopedDirLookup dir(&dm, "Open");
     ASSERT_TRUE(dir.good());
@@ -1389,13 +1389,13 @@ TEST(SyncableDirectoryManager, ThreadOpenTest) {
 struct Step {
   Step() : condvar(&mutex), number(0) {}
 
-  Lock mutex;
-  ConditionVariable condvar;
+  base::Lock mutex;
+  base::ConditionVariable condvar;
   int number;
   int64 metahandle;
 };
 
-class ThreadBugDelegate : public PlatformThread::Delegate {
+class ThreadBugDelegate : public base::PlatformThread::Delegate {
  public:
   // a role is 0 or 1, meaning this thread does the odd or event steps.
   ThreadBugDelegate(int role, Step* step, DirectoryManager* dirman)
@@ -1409,7 +1409,7 @@ class ThreadBugDelegate : public PlatformThread::Delegate {
   // PlatformThread::Delegate methods:
   virtual void ThreadMain() {
     const std::string dirname = "ThreadBug1";
-    AutoLock scoped_lock(step_->mutex);
+    base::AutoLock scoped_lock(step_->mutex);
 
     while (step_->number < 3) {
       while (step_->number % 2 != role_) {
@@ -1457,14 +1457,16 @@ TEST(SyncableDirectoryManager, ThreadBug1) {
   ThreadBugDelegate thread_delegate_1(0, &step, &dirman);
   ThreadBugDelegate thread_delegate_2(1, &step, &dirman);
 
-  PlatformThreadHandle thread_handle_1;
-  PlatformThreadHandle thread_handle_2;
+  base::PlatformThreadHandle thread_handle_1;
+  base::PlatformThreadHandle thread_handle_2;
 
-  ASSERT_TRUE(PlatformThread::Create(0, &thread_delegate_1, &thread_handle_1));
-  ASSERT_TRUE(PlatformThread::Create(0, &thread_delegate_2, &thread_handle_2));
+  ASSERT_TRUE(
+      base::PlatformThread::Create(0, &thread_delegate_1, &thread_handle_1));
+  ASSERT_TRUE(
+      base::PlatformThread::Create(0, &thread_delegate_2, &thread_handle_2));
 
-  PlatformThread::Join(thread_handle_1);
-  PlatformThread::Join(thread_handle_2);
+  base::PlatformThread::Join(thread_handle_1);
+  base::PlatformThread::Join(thread_handle_2);
 }
 
 
@@ -1480,7 +1482,7 @@ class DirectoryKernelStalenessBugDelegate : public ThreadBugDelegate {
   virtual void ThreadMain() {
     const char test_bytes[] = "test data";
     const std::string dirname = "DirectoryKernelStalenessBug";
-    AutoLock scoped_lock(step_->mutex);
+    base::AutoLock scoped_lock(step_->mutex);
     const Id jeff_id = TestIdFactory::FromNumber(100);
 
     while (step_->number < 4) {
@@ -1552,17 +1554,19 @@ TEST(SyncableDirectoryManager, DirectoryKernelStalenessBug) {
   DirectoryKernelStalenessBugDelegate thread_delegate_1(0, &step, &dirman);
   DirectoryKernelStalenessBugDelegate thread_delegate_2(1, &step, &dirman);
 
-  PlatformThreadHandle thread_handle_1;
-  PlatformThreadHandle thread_handle_2;
+  base::PlatformThreadHandle thread_handle_1;
+  base::PlatformThreadHandle thread_handle_2;
 
-  ASSERT_TRUE(PlatformThread::Create(0, &thread_delegate_1, &thread_handle_1));
-  ASSERT_TRUE(PlatformThread::Create(0, &thread_delegate_2, &thread_handle_2));
+  ASSERT_TRUE(
+      base::PlatformThread::Create(0, &thread_delegate_1, &thread_handle_1));
+  ASSERT_TRUE(
+      base::PlatformThread::Create(0, &thread_delegate_2, &thread_handle_2));
 
-  PlatformThread::Join(thread_handle_1);
-  PlatformThread::Join(thread_handle_2);
+  base::PlatformThread::Join(thread_handle_1);
+  base::PlatformThread::Join(thread_handle_2);
 }
 
-class StressTransactionsDelegate : public PlatformThread::Delegate {
+class StressTransactionsDelegate : public base::PlatformThread::Delegate {
  public:
   StressTransactionsDelegate(DirectoryManager* dm,
                              const std::string& dirname,
@@ -1588,7 +1592,7 @@ class StressTransactionsDelegate : public PlatformThread::Delegate {
       if (rand_action < 4 && !path_name.empty()) {
         ReadTransaction trans(dir, __FILE__, __LINE__);
         CHECK(1 == CountEntriesWithName(&trans, trans.root_id(), path_name));
-        PlatformThread::Sleep(rand() % 10);
+        base::PlatformThread::Sleep(rand() % 10);
       } else {
         std::string unique_name = StringPrintf("%d.%d", thread_number_,
                                                entry_count++);
@@ -1596,7 +1600,7 @@ class StressTransactionsDelegate : public PlatformThread::Delegate {
         WriteTransaction trans(dir, UNITTEST, __FILE__, __LINE__);
         MutableEntry e(&trans, CREATE, trans.root_id(), path_name);
         CHECK(e.good());
-        PlatformThread::Sleep(rand() % 20);
+        base::PlatformThread::Sleep(rand() % 20);
         e.Put(IS_UNSYNCED, true);
         if (e.Put(ID, TestIdFactory::FromNumber(rand())) &&
             e.Get(ID).ServerKnows() && !e.Get(ID).IsRoot()) {
@@ -1616,18 +1620,18 @@ TEST(SyncableDirectory, StressTransactions) {
   dirman.Open(dirname);
 
   const int kThreadCount = 7;
-  PlatformThreadHandle threads[kThreadCount];
+  base::PlatformThreadHandle threads[kThreadCount];
   scoped_ptr<StressTransactionsDelegate> thread_delegates[kThreadCount];
 
   for (int i = 0; i < kThreadCount; ++i) {
     thread_delegates[i].reset(
         new StressTransactionsDelegate(&dirman, dirname, i));
-    ASSERT_TRUE(
-        PlatformThread::Create(0, thread_delegates[i].get(), &threads[i]));
+    ASSERT_TRUE(base::PlatformThread::Create(
+        0, thread_delegates[i].get(), &threads[i]));
   }
 
   for (int i = 0; i < kThreadCount; ++i) {
-    PlatformThread::Join(threads[i]);
+    base::PlatformThread::Join(threads[i]);
   }
 
   dirman.Close(dirname);
diff --git a/chrome/browser/sync/test_profile_sync_service.h b/chrome/browser/sync/test_profile_sync_service.h
index f5da3d6..2615b24 100644
--- a/chrome/browser/sync/test_profile_sync_service.h
+++ b/chrome/browser/sync/test_profile_sync_service.h
@@ -112,6 +112,12 @@ class SyncBackendHostForProfileSyncTest : public SyncBackendHost {
     }
   }
 
+  virtual void ConfigureDataTypes(const syncable::ModelTypeSet& types,
+      CancelableTask* ready_task) {
+    SetAutofillMigrationState(syncable::MIGRATED);
+    SyncBackendHost::ConfigureDataTypes(types, ready_task);
+  }
+
   virtual void HandleInitializationCompletedOnFrontendLoop() {
     set_syncapi_initialized();  // Need to do this asap so task below works.
 
diff --git a/chrome/browser/sync/tools/sync_listen_notifications.cc b/chrome/browser/sync/tools/sync_listen_notifications.cc
index d15ded3..0f66c27 100644
--- a/chrome/browser/sync/tools/sync_listen_notifications.cc
+++ b/chrome/browser/sync/tools/sync_listen_notifications.cc
@@ -299,7 +299,6 @@ int main(int argc, char* argv[]) {
   xmpp_client_settings.set_server(addr);
 
   net::CertVerifier cert_verifier;
-
   MessageLoopForIO message_loop;
 
   // Connect and listen.
diff --git a/chrome/browser/sync/util/channel.h b/chrome/browser/sync/util/channel.h
index a21f6ea..88ddfc4 100644
--- a/chrome/browser/sync/util/channel.h
+++ b/chrome/browser/sync/util/channel.h
@@ -52,7 +52,7 @@
 
 #include "base/lock.h"
 #include "base/observer_list.h"
-#include "base/platform_thread.h"
+#include "base/threading/platform_thread.h"
 
 namespace browser_sync {
 
@@ -106,7 +106,7 @@ class Channel {
   void RemoveObserver(ChannelEventHandler<EventType>* observer) {
     // This can be called in response to a notification, so we may already have
     // locked this channel on this thread.
-    bool need_lock = (locking_thread_ != PlatformThread::CurrentId());
+    bool need_lock = (locking_thread_ != base::PlatformThread::CurrentId());
     if (need_lock)
       event_handlers_mutex_.Acquire();
 
@@ -121,7 +121,7 @@ class Channel {
 
     // This may result in an observer trying to remove itself, so keep track
     // of the thread we're locked on.
-    locking_thread_ = PlatformThread::CurrentId();
+    locking_thread_ = base::PlatformThread::CurrentId();
 
     ChannelObserverList::Iterator it(event_handlers_);
     EventHandler* obs;
@@ -136,7 +136,7 @@ class Channel {
 
  private:
   Lock event_handlers_mutex_;
-  PlatformThreadId locking_thread_;
+  base::PlatformThreadId locking_thread_;
   ObserverList<EventHandler> event_handlers_;
 };
 
diff --git a/chrome/browser/sync/util/extensions_activity_monitor_unittest.cc b/chrome/browser/sync/util/extensions_activity_monitor_unittest.cc
index d5f88d4..b85256e 100644
--- a/chrome/browser/sync/util/extensions_activity_monitor_unittest.cc
+++ b/chrome/browser/sync/util/extensions_activity_monitor_unittest.cc
@@ -6,7 +6,7 @@
 
 #include "base/file_path.h"
 #include "base/string_util.h"
-#include "base/waitable_event.h"
+#include "base/synchronization/waitable_event.h"
 #include "base/values.h"
 #include "chrome/browser/browser_thread.h"
 #include "chrome/browser/extensions/extension_bookmarks_module.h"