[Sync] Add Location parameter to Read/WriteTransactions

Also add to SyncChangeProcessor and SyncableService.

BUG=
TEST=

Review URL: http://codereview.chromium.org/7189004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@89556 0039d316-1c4b-4281-b951-d872f2087c98

54 files changed, 532 insertions, 484 deletions

diff --git a/chrome/browser/sync/abstract_profile_sync_service_test.cc b/chrome/browser/sync/abstract_profile_sync_service_test.cc
index f7c5f66..2dcace3 100644
--- a/chrome/browser/sync/abstract_profile_sync_service_test.cc
+++ b/chrome/browser/sync/abstract_profile_sync_service_test.cc
@@ -48,7 +48,7 @@ bool ProfileSyncServiceTestHelper::CreateRoot(
 
   std::string tag_name = GetTagForType(model_type);
 
-  WriteTransaction wtrans(dir, UNITTEST, FROM_HERE);
+  WriteTransaction wtrans(FROM_HERE, UNITTEST, dir);
   MutableEntry node(&wtrans,
                     CREATE,
                     wtrans.root_id(),
diff --git a/chrome/browser/sync/api/sync_change_processor.h b/chrome/browser/sync/api/sync_change_processor.h
index e16d313..80be610 100644
--- a/chrome/browser/sync/api/sync_change_processor.h
+++ b/chrome/browser/sync/api/sync_change_processor.h
@@ -10,13 +10,18 @@
 
 class SyncChange;
 
+namespace tracked_objects {
+class Location;
+}  // namespace tracked_objects
+
 typedef std::vector<SyncChange> SyncChangeList;
 
 // An interface for services that handle receiving SyncChanges.
 class SyncChangeProcessor {
  public:
   // Process a list of SyncChanges.
-  virtual void ProcessSyncChanges(const SyncChangeList& change_list) = 0;
+  virtual void ProcessSyncChanges(const tracked_objects::Location& from_here,
+                                  const SyncChangeList& change_list) = 0;
  protected:
   virtual ~SyncChangeProcessor();
 };
diff --git a/chrome/browser/sync/api/syncable_service.h b/chrome/browser/sync/api/syncable_service.h
index 7f4de39..3c40975 100644
--- a/chrome/browser/sync/api/syncable_service.h
+++ b/chrome/browser/sync/api/syncable_service.h
@@ -8,6 +8,7 @@
 
 #include <vector>
 
+#include "base/compiler_specific.h"
 #include "chrome/browser/sync/syncable/model_type.h"
 #include "chrome/browser/sync/api/sync_change_processor.h"
 #include "chrome/browser/sync/api/sync_data.h"
@@ -39,7 +40,9 @@ class SyncableService : public SyncChangeProcessor {
 
   // SyncChangeProcessor interface.
   // Process a list of new SyncChanges and update the local data as necessary.
-  virtual void ProcessSyncChanges(const SyncChangeList& change_list) = 0;
+  virtual void ProcessSyncChanges(
+      const tracked_objects::Location& from_here,
+      const SyncChangeList& change_list) OVERRIDE = 0;
 
  protected:
   virtual ~SyncableService();
diff --git a/chrome/browser/sync/api/syncable_service_mock.h b/chrome/browser/sync/api/syncable_service_mock.h
index 5390e4a..29c5e9b 100644
--- a/chrome/browser/sync/api/syncable_service_mock.h
+++ b/chrome/browser/sync/api/syncable_service_mock.h
@@ -6,6 +6,7 @@
 #define CHROME_BROWSER_SYNC_API_SYNCABLE_SERVICE_MOCK_H_
 #pragma once
 
+#include "base/tracked.h"
 #include "chrome/browser/sync/api/syncable_service.h"
 #include "chrome/browser/sync/api/sync_change.h"
 #include "testing/gmock/include/gmock/gmock.h"
@@ -16,12 +17,12 @@ class SyncableServiceMock : public SyncableService {
   virtual ~SyncableServiceMock();
 
   MOCK_METHOD3(MergeDataAndStartSyncing, bool(
-      syncable::ModelType type,
-      const SyncDataList& initial_sync_data,
+      syncable::ModelType, const SyncDataList&,
       SyncChangeProcessor* sync_processor));
-  MOCK_METHOD1(StopSyncing, void(syncable::ModelType type));
-  MOCK_CONST_METHOD1(GetAllSyncData, SyncDataList(syncable::ModelType type));
-  MOCK_METHOD1(ProcessSyncChanges, void(const SyncChangeList& change_list));
+  MOCK_METHOD1(StopSyncing, void(syncable::ModelType));
+  MOCK_CONST_METHOD1(GetAllSyncData, SyncDataList(syncable::ModelType));
+  MOCK_METHOD2(ProcessSyncChanges,
+               void(const tracked_objects::Location&, const SyncChangeList&));
 };
 
 #endif  // CHROME_BROWSER_SYNC_API_SYNCABLE_SERVICE_MOCK_H_
diff --git a/chrome/browser/sync/engine/apply_updates_command.cc b/chrome/browser/sync/engine/apply_updates_command.cc
index 670e171..40ce3ec 100644
--- a/chrome/browser/sync/engine/apply_updates_command.cc
+++ b/chrome/browser/sync/engine/apply_updates_command.cc
@@ -24,7 +24,7 @@ void ApplyUpdatesCommand::ModelChangingExecuteImpl(SyncSession* session) {
     LOG(ERROR) << "Scoped dir lookup failed!";
     return;
   }
-  syncable::WriteTransaction trans(dir, syncable::SYNCER, FROM_HERE);
+  syncable::WriteTransaction trans(FROM_HERE, syncable::SYNCER, dir);
   syncable::Directory::UnappliedUpdateMetaHandles handles;
   dir->GetUnappliedUpdateMetaHandles(&trans, &handles);
 
diff --git a/chrome/browser/sync/engine/apply_updates_command_unittest.cc b/chrome/browser/sync/engine/apply_updates_command_unittest.cc
index 1e091b1..368cf15 100644
--- a/chrome/browser/sync/engine/apply_updates_command_unittest.cc
+++ b/chrome/browser/sync/engine/apply_updates_command_unittest.cc
@@ -56,7 +56,7 @@ class ApplyUpdatesCommandTest : public SyncerCommandTest {
                                         const string& parent_id) {
     ScopedDirLookup dir(syncdb()->manager(), syncdb()->name());
     ASSERT_TRUE(dir.good());
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry entry(&trans, syncable::CREATE_NEW_UPDATE_ITEM,
         Id::CreateFromServerId(item_id));
     ASSERT_TRUE(entry.good());
@@ -77,7 +77,7 @@ class ApplyUpdatesCommandTest : public SyncerCommandTest {
                               bool is_unique) {
     ScopedDirLookup dir(syncdb()->manager(), syncdb()->name());
     ASSERT_TRUE(dir.good());
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry entry(&trans, syncable::CREATE_NEW_UPDATE_ITEM,
         Id::CreateFromServerId(item_id));
     ASSERT_TRUE(entry.good());
@@ -103,7 +103,7 @@ class ApplyUpdatesCommandTest : public SyncerCommandTest {
                           int64* metahandle_out) {
     ScopedDirLookup dir(syncdb()->manager(), syncdb()->name());
     ASSERT_TRUE(dir.good());
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     Id predecessor_id = dir->GetLastChildId(&trans, parent_id);
     MutableEntry entry(&trans, syncable::CREATE, parent_id, name);
     ASSERT_TRUE(entry.good());
@@ -222,7 +222,7 @@ TEST_F(ApplyUpdatesCommandTest, DecryptablePassword) {
       // know it's safe.
       ScopedDirLookup dir(syncdb()->manager(), syncdb()->name());
       ASSERT_TRUE(dir.good());
-      ReadTransaction trans(dir, FROM_HERE);
+      ReadTransaction trans(FROM_HERE, dir);
       cryptographer =
           session()->context()->directory_manager()->GetCryptographer(&trans);
   }
@@ -286,7 +286,7 @@ TEST_F(ApplyUpdatesCommandTest, SomeUndecryptablePassword) {
     {
       ScopedDirLookup dir(syncdb()->manager(), syncdb()->name());
       ASSERT_TRUE(dir.good());
-      ReadTransaction trans(dir, FROM_HERE);
+      ReadTransaction trans(FROM_HERE, dir);
       Cryptographer* cryptographer =
           session()->context()->directory_manager()->GetCryptographer(&trans);
 
@@ -343,7 +343,7 @@ TEST_F(ApplyUpdatesCommandTest, NigoriUpdate) {
   {
     ScopedDirLookup dir(syncdb()->manager(), syncdb()->name());
     ASSERT_TRUE(dir.good());
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     cryptographer =
         session()->context()->directory_manager()->GetCryptographer(&trans);
     EXPECT_EQ(encrypted_types, cryptographer->GetEncryptedTypes());
@@ -388,7 +388,7 @@ TEST_F(ApplyUpdatesCommandTest, EncryptUnsyncedChanges) {
   {
     ScopedDirLookup dir(syncdb()->manager(), syncdb()->name());
     ASSERT_TRUE(dir.good());
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     cryptographer =
         session()->context()->directory_manager()->GetCryptographer(&trans);
     EXPECT_EQ(encrypted_types, cryptographer->GetEncryptedTypes());
@@ -439,7 +439,7 @@ TEST_F(ApplyUpdatesCommandTest, EncryptUnsyncedChanges) {
     // Ensure we have unsynced nodes that aren't properly encrypted.
     ScopedDirLookup dir(syncdb()->manager(), syncdb()->name());
     ASSERT_TRUE(dir.good());
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     EXPECT_FALSE(VerifyUnsyncedChangesAreEncrypted(&trans, encrypted_types));
 
     Syncer::UnsyncedMetaHandles handles;
@@ -464,7 +464,7 @@ TEST_F(ApplyUpdatesCommandTest, EncryptUnsyncedChanges) {
   {
     ScopedDirLookup dir(syncdb()->manager(), syncdb()->name());
     ASSERT_TRUE(dir.good());
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
 
     // If ProcessUnsyncedChangesForEncryption worked, all our unsynced changes
     // should be encrypted now.
@@ -486,7 +486,7 @@ TEST_F(ApplyUpdatesCommandTest, CannotEncryptUnsyncedChanges) {
   {
     ScopedDirLookup dir(syncdb()->manager(), syncdb()->name());
     ASSERT_TRUE(dir.good());
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     cryptographer =
         session()->context()->directory_manager()->GetCryptographer(&trans);
     EXPECT_EQ(encrypted_types, cryptographer->GetEncryptedTypes());
@@ -539,7 +539,7 @@ TEST_F(ApplyUpdatesCommandTest, CannotEncryptUnsyncedChanges) {
     // Ensure we have unsynced nodes that aren't properly encrypted.
     ScopedDirLookup dir(syncdb()->manager(), syncdb()->name());
     ASSERT_TRUE(dir.good());
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     EXPECT_FALSE(VerifyUnsyncedChangesAreEncrypted(&trans, encrypted_types));
     Syncer::UnsyncedMetaHandles handles;
     SyncerUtil::GetUnsyncedEntries(&trans, &handles);
@@ -566,7 +566,7 @@ TEST_F(ApplyUpdatesCommandTest, CannotEncryptUnsyncedChanges) {
     // Ensure the unsynced nodes are still not encrypted.
     ScopedDirLookup dir(syncdb()->manager(), syncdb()->name());
     ASSERT_TRUE(dir.good());
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
 
     // Since we're in conflict, the specifics don't reflect the unapplied
     // changes.
diff --git a/chrome/browser/sync/engine/build_and_process_conflict_sets_command.cc b/chrome/browser/sync/engine/build_and_process_conflict_sets_command.cc
index 933dfee..09147d4 100644
--- a/chrome/browser/sync/engine/build_and_process_conflict_sets_command.cc
+++ b/chrome/browser/sync/engine/build_and_process_conflict_sets_command.cc
@@ -44,7 +44,7 @@ bool BuildAndProcessConflictSetsCommand::BuildAndProcessConflictSets(
     return false;
   bool had_single_direction_sets = false;
   {  // Scope for transaction.
-    syncable::WriteTransaction trans(dir, syncable::SYNCER, FROM_HERE);
+    syncable::WriteTransaction trans(FROM_HERE, syncable::SYNCER, dir);
     BuildConflictSets(&trans,
         session->status_controller()->mutable_conflict_progress());
     had_single_direction_sets = ProcessSingleDirectionConflictSets(&trans,
diff --git a/chrome/browser/sync/engine/conflict_resolver.cc b/chrome/browser/sync/engine/conflict_resolver.cc
index 0e1b9d7..3df973c 100644
--- a/chrome/browser/sync/engine/conflict_resolver.cc
+++ b/chrome/browser/sync/engine/conflict_resolver.cc
@@ -433,7 +433,7 @@ bool ConflictResolver::LogAndSignalIfConflictStuck(
 
 bool ConflictResolver::ResolveSimpleConflicts(const ScopedDirLookup& dir,
                                               StatusController* status) {
-  WriteTransaction trans(dir, syncable::SYNCER, FROM_HERE);
+  WriteTransaction trans(FROM_HERE, syncable::SYNCER, dir);
   bool forward_progress = false;
   const ConflictProgress& progress = status->conflict_progress();
   // First iterate over simple conflict items (those that belong to no set).
@@ -478,7 +478,7 @@ bool ConflictResolver::ResolveConflicts(const ScopedDirLookup& dir,
   bool rv = false;
   if (ResolveSimpleConflicts(dir, status))
     rv = true;
-  WriteTransaction trans(dir, syncable::SYNCER, FROM_HERE);
+  WriteTransaction trans(FROM_HERE, syncable::SYNCER, dir);
   set<ConflictSet*>::const_iterator set_it;
   for (set_it = progress.ConflictSetsBegin();
        set_it != progress.ConflictSetsEnd();
diff --git a/chrome/browser/sync/engine/post_commit_message_command.cc b/chrome/browser/sync/engine/post_commit_message_command.cc
index babfd36..abc4ee1 100644
--- a/chrome/browser/sync/engine/post_commit_message_command.cc
+++ b/chrome/browser/sync/engine/post_commit_message_command.cc
@@ -35,7 +35,7 @@ void PostCommitMessageCommand::ExecuteImpl(sessions::SyncSession* session) {
     // Not to be confused with IS_UNSYNCED, this bit is used to detect local
     // changes to items that happen during the server Commit operation.
     status->increment_num_consecutive_errors();
-    syncable::WriteTransaction trans(dir, syncable::SYNCER, FROM_HERE);
+    syncable::WriteTransaction trans(FROM_HERE, syncable::SYNCER, dir);
     const vector<syncable::Id>& commit_ids = status->commit_ids();
     for (size_t i = 0; i < commit_ids.size(); i++) {
       syncable::MutableEntry entry(&trans, syncable::GET_BY_ID, commit_ids[i]);
diff --git a/chrome/browser/sync/engine/process_commit_response_command.cc b/chrome/browser/sync/engine/process_commit_response_command.cc
index 6e7293d..e5c73a7 100644
--- a/chrome/browser/sync/engine/process_commit_response_command.cc
+++ b/chrome/browser/sync/engine/process_commit_response_command.cc
@@ -137,7 +137,7 @@ void ProcessCommitResponseCommand::ProcessCommitResponse(
   ConflictProgress* conflict_progress = status->mutable_conflict_progress();
   OrderedCommitSet::Projection proj = status->commit_id_projection();
   if (!proj.empty()) { // Scope for WriteTransaction.
-    WriteTransaction trans(dir, SYNCER, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, SYNCER, dir);
     for (size_t i = 0; i < proj.size(); i++) {
       CommitResponse::ResponseType response_type =
           ProcessSingleCommitResponse(&trans, cr.entryresponse(proj[i]),
diff --git a/chrome/browser/sync/engine/process_commit_response_command_unittest.cc b/chrome/browser/sync/engine/process_commit_response_command_unittest.cc
index 4c8c796..bfa97f2 100644
--- a/chrome/browser/sync/engine/process_commit_response_command_unittest.cc
+++ b/chrome/browser/sync/engine/process_commit_response_command_unittest.cc
@@ -91,7 +91,7 @@ class ProcessCommitResponseCommandTestWithParam
                           int64* metahandle_out) {
     ScopedDirLookup dir(syncdb()->manager(), syncdb()->name());
     ASSERT_TRUE(dir.good());
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     Id predecessor_id = dir->GetLastChildId(&trans, parent_id);
     MutableEntry entry(&trans, syncable::CREATE, parent_id, name);
     ASSERT_TRUE(entry.good());
@@ -137,7 +137,7 @@ class ProcessCommitResponseCommandTestWithParam
 
     ScopedDirLookup dir(syncdb()->manager(), syncdb()->name());
     ASSERT_TRUE(dir.good());
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry entry(&trans, syncable::GET_BY_ID, item_id);
     ASSERT_TRUE(entry.good());
     entry.Put(syncable::SYNCING, true);
@@ -233,7 +233,7 @@ TEST_F(ProcessCommitResponseCommandTest, MultipleCommitIdProjections) {
 
   ScopedDirLookup dir(syncdb()->manager(), syncdb()->name());
   ASSERT_TRUE(dir.good());
-  ReadTransaction trans(dir, FROM_HERE);
+  ReadTransaction trans(FROM_HERE, dir);
   Id new_fid = dir->GetFirstChildId(&trans, id_factory_.root());
   ASSERT_FALSE(new_fid.IsRoot());
   EXPECT_TRUE(new_fid.ServerKnows());
@@ -287,7 +287,7 @@ TEST_F(ProcessCommitResponseCommandTest, NewFolderCommitKeepsChildOrder) {
   {
     ScopedDirLookup dir(syncdb()->manager(), syncdb()->name());
     ASSERT_TRUE(dir.good());
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     ASSERT_EQ(folder_id, dir->GetFirstChildId(&trans, id_factory_.root()));
   }
 
@@ -320,7 +320,7 @@ TEST_F(ProcessCommitResponseCommandTest, NewFolderCommitKeepsChildOrder) {
 
   ScopedDirLookup dir(syncdb()->manager(), syncdb()->name());
   ASSERT_TRUE(dir.good());
-  ReadTransaction trans(dir, FROM_HERE);
+  ReadTransaction trans(FROM_HERE, dir);
   // Lookup the parent folder by finding a child of the root.  We can't use
   // folder_id here, because it changed during the commit.
   Id new_fid = dir->GetFirstChildId(&trans, id_factory_.root());
diff --git a/chrome/browser/sync/engine/process_updates_command.cc b/chrome/browser/sync/engine/process_updates_command.cc
index f11db79..85accd3 100644
--- a/chrome/browser/sync/engine/process_updates_command.cc
+++ b/chrome/browser/sync/engine/process_updates_command.cc
@@ -98,7 +98,7 @@ ServerUpdateProcessingResult ProcessUpdatesCommand::ProcessUpdate(
   syncable::Id server_id = update.id();
   const std::string name = SyncerProtoUtil::NameFromSyncEntity(update);
 
-  syncable::WriteTransaction trans(dir, syncable::SYNCER, FROM_HERE);
+  syncable::WriteTransaction trans(FROM_HERE, syncable::SYNCER, dir);
 
   // Look to see if there's a local item that should recieve this update,
   // maybe due to a duplicate client tag or a lost commit response.
diff --git a/chrome/browser/sync/engine/syncapi.cc b/chrome/browser/sync/engine/syncapi.cc
index 690905d..bcc19fa 100644
--- a/chrome/browser/sync/engine/syncapi.cc
+++ b/chrome/browser/sync/engine/syncapi.cc
@@ -964,11 +964,12 @@ bool ReadNode::InitByTagLookup(const std::string& tag) {
 
 //////////////////////////////////////////////////////////////////////////
 // ReadTransaction member definitions
-ReadTransaction::ReadTransaction(UserShare* share)
+ReadTransaction::ReadTransaction(const tracked_objects::Location& from_here,
+                                 UserShare* share)
     : BaseTransaction(share),
       transaction_(NULL),
       close_transaction_(true) {
-  transaction_ = new syncable::ReadTransaction(GetLookup(), FROM_HERE);
+  transaction_ = new syncable::ReadTransaction(from_here, GetLookup());
 }
 
 ReadTransaction::ReadTransaction(UserShare* share,
@@ -989,11 +990,12 @@ syncable::BaseTransaction* ReadTransaction::GetWrappedTrans() const {
 
 //////////////////////////////////////////////////////////////////////////
 // WriteTransaction member definitions
-WriteTransaction::WriteTransaction(UserShare* share)
+WriteTransaction::WriteTransaction(const tracked_objects::Location& from_here,
+                                   UserShare* share)
     : BaseTransaction(share),
       transaction_(NULL) {
-  transaction_ = new syncable::WriteTransaction(GetLookup(), syncable::SYNCAPI,
-                                                FROM_HERE);
+  transaction_ = new syncable::WriteTransaction(from_here, syncable::SYNCAPI,
+                                                GetLookup());
 }
 
 WriteTransaction::~WriteTransaction() {
@@ -1798,7 +1800,7 @@ bool SyncManager::SyncInternal::Init(
 void SyncManager::SyncInternal::BootstrapEncryption(
     const std::string& restored_key_for_bootstrapping) {
   // Cryptographer should only be accessed while holding a transaction.
-  ReadTransaction trans(GetUserShare());
+  ReadTransaction trans(FROM_HERE, GetUserShare());
   Cryptographer* cryptographer = trans.GetCryptographer();
 
   // Set the bootstrap token before bailing out if nigori node is not there.
@@ -1816,7 +1818,7 @@ bool SyncManager::SyncInternal::UpdateCryptographerFromNigori() {
   if (!lookup->initial_sync_ended_for_type(syncable::NIGORI))
     return false;  // Should only happen during first time sync.
 
-  ReadTransaction trans(GetUserShare());
+  ReadTransaction trans(FROM_HERE, GetUserShare());
   Cryptographer* cryptographer = trans.GetCryptographer();
 
   ReadNode node(&trans);
@@ -1965,7 +1967,7 @@ void SyncManager::SyncInternal::SetPassphrase(
   }
 
   // All accesses to the cryptographer are protected by a transaction.
-  WriteTransaction trans(GetUserShare());
+  WriteTransaction trans(FROM_HERE, GetUserShare());
   Cryptographer* cryptographer = trans.GetCryptographer();
   KeyParams params = {"localhost", "dummy", passphrase};
 
@@ -2027,7 +2029,7 @@ void SyncManager::SyncInternal::SetPassphrase(
 }
 
 bool SyncManager::SyncInternal::IsUsingExplicitPassphrase() {
-  ReadTransaction trans(&share_);
+  ReadTransaction trans(FROM_HERE, &share_);
   ReadNode node(&trans);
   if (!node.InitByTagLookup(kNigoriTag)) {
     // TODO(albertb): Plumb an UnrecoverableError all the way back to the PSS.
@@ -2044,7 +2046,7 @@ void SyncManager::SyncInternal::EncryptDataTypes(
   VLOG(1) << "Attempting to encrypt datatypes "
           << syncable::ModelTypeSetToString(encrypted_types);
 
-  WriteTransaction trans(GetUserShare());
+  WriteTransaction trans(FROM_HERE, GetUserShare());
   WriteNode node(&trans);
   if (!node.InitByTagLookup(kNigoriTag)) {
     NOTREACHED() << "Unable to set encrypted datatypes because Nigori node not "
@@ -2473,7 +2475,7 @@ void SyncManager::SyncInternal::OnSyncEngineEvent(
     {
       // Check to see if we need to notify the frontend that we have newly
       // encrypted types or that we require a passphrase.
-      sync_api::ReadTransaction trans(GetUserShare());
+      sync_api::ReadTransaction trans(FROM_HERE, GetUserShare());
       syncable::ModelTypeSet encrypted_types = GetEncryptedTypes(&trans);
       syncable::ModelTypeSet encrypted_and_enabled_types;
       for (syncable::ModelTypeSet::iterator iter = encrypted_types.begin();
@@ -2691,7 +2693,7 @@ browser_sync::JsArgList
 browser_sync::JsArgList
     SyncManager::SyncInternal::GetRootNodeDetails(
         const browser_sync::JsArgList& args) {
-  ReadTransaction trans(GetUserShare());
+  ReadTransaction trans(FROM_HERE, GetUserShare());
   ReadNode root(&trans);
   root.InitByRootLookup();
   ListValue return_args;
@@ -2722,7 +2724,7 @@ browser_sync::JsArgList GetNodeInfoById(
   ListValue* node_summaries = new ListValue();
   return_args.Append(node_summaries);
   ListValue* id_list = NULL;
-  ReadTransaction trans(user_share);
+  ReadTransaction trans(FROM_HERE, user_share);
   if (args.Get().GetList(0, &id_list)) {
     CHECK(id_list);
     for (size_t i = 0; i < id_list->GetSize(); ++i) {
@@ -2762,7 +2764,7 @@ browser_sync::JsArgList SyncManager::SyncInternal::
   return_args.Append(child_ids);
   int64 id = GetId(args.Get(), 0);
   if (id != kInvalidId) {
-    ReadTransaction trans(GetUserShare());
+    ReadTransaction trans(FROM_HERE, GetUserShare());
     syncable::Directory::ChildHandles child_handles;
     trans.GetLookup()->GetChildHandlesByHandle(trans.GetWrappedTrans(),
                                                id, &child_handles);
@@ -2793,7 +2795,7 @@ browser_sync::JsArgList SyncManager::SyncInternal::
   ListValue* result = new ListValue();
   return_args.Append(result);
 
-  ReadTransaction trans(GetUserShare());
+  ReadTransaction trans(FROM_HERE, GetUserShare());
   std::vector<const syncable::EntryKernel*> entry_kernels;
   trans.GetLookup()->GetAllEntryKernels(trans.GetWrappedTrans(),
                                         &entry_kernels);
@@ -2967,18 +2969,18 @@ void SyncManager::RefreshEncryption() {
 }
 
 syncable::ModelTypeSet SyncManager::GetEncryptedDataTypes() const {
-  sync_api::ReadTransaction trans(GetUserShare());
+  sync_api::ReadTransaction trans(FROM_HERE, GetUserShare());
   return GetEncryptedTypes(&trans);
 }
 
 bool SyncManager::HasUnsyncedItems() const {
-  sync_api::ReadTransaction trans(GetUserShare());
+  sync_api::ReadTransaction trans(FROM_HERE, GetUserShare());
   return (trans.GetWrappedTrans()->directory()->unsynced_entity_count() != 0);
 }
 
 void SyncManager::LogUnsyncedItems(int level) const {
   std::vector<int64> unsynced_handles;
-  sync_api::ReadTransaction trans(GetUserShare());
+  sync_api::ReadTransaction trans(FROM_HERE, GetUserShare());
   trans.GetWrappedTrans()->directory()->GetUnsyncedMetaHandles(
       trans.GetWrappedTrans(), &unsynced_handles);
 
diff --git a/chrome/browser/sync/engine/syncapi.h b/chrome/browser/sync/engine/syncapi.h
index 8264f41..94d7e36 100644
--- a/chrome/browser/sync/engine/syncapi.h
+++ b/chrome/browser/sync/engine/syncapi.h
@@ -101,6 +101,10 @@ class ThemeSpecifics;
 class TypedUrlSpecifics;
 }
 
+namespace tracked_objects {
+class Location;
+}  // namespace tracked_objects
+
 namespace sync_api {
 
 class BaseTransaction;
@@ -552,7 +556,8 @@ class BaseTransaction {
 class ReadTransaction : public BaseTransaction {
  public:
   // Start a new read-only transaction on the specified repository.
-  explicit ReadTransaction(UserShare* share);
+  ReadTransaction(const tracked_objects::Location& from_here,
+                  UserShare* share);
 
   // Resume the middle of a transaction. Will not close transaction.
   ReadTransaction(UserShare* share, syncable::BaseTransaction* trans);
@@ -576,7 +581,8 @@ class ReadTransaction : public BaseTransaction {
 class WriteTransaction : public BaseTransaction {
  public:
   // Start a new read/write transaction.
-  explicit WriteTransaction(UserShare* share);
+  explicit WriteTransaction(const tracked_objects::Location& from_here,
+                            UserShare* share);
   virtual ~WriteTransaction();
 
   // Provide access to the syncable.h transaction from the API WriteNode.
diff --git a/chrome/browser/sync/engine/syncapi_mock.h b/chrome/browser/sync/engine/syncapi_mock.h
index ada0a56..8e71aa8 100644
--- a/chrome/browser/sync/engine/syncapi_mock.h
+++ b/chrome/browser/sync/engine/syncapi_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.
 
@@ -16,9 +16,10 @@ using sync_api::WriteTransaction;
 
 class MockWriteTransaction : public sync_api::WriteTransaction {
  public:
-  explicit MockWriteTransaction(Directory* directory)
+  MockWriteTransaction(const tracked_objects::Location& from_here,
+                       Directory* directory)
      : sync_api::WriteTransaction() {
-    this->SetTransaction(new MockSyncableWriteTransaction(directory));
+    SetTransaction(new MockSyncableWriteTransaction(from_here, directory));
   }
 };
 
diff --git a/chrome/browser/sync/engine/syncapi_unittest.cc b/chrome/browser/sync/engine/syncapi_unittest.cc
index 532e020..90ffe3f 100644
--- a/chrome/browser/sync/engine/syncapi_unittest.cc
+++ b/chrome/browser/sync/engine/syncapi_unittest.cc
@@ -87,7 +87,7 @@ void ExpectInt64Value(int64 expected_value,
 int64 MakeNode(UserShare* share,
                ModelType model_type,
                const std::string& client_tag) {
-  WriteTransaction trans(share);
+  WriteTransaction trans(FROM_HERE, share);
   ReadNode root_node(&trans);
   root_node.InitByRootLookup();
   WriteNode node(&trans);
@@ -102,7 +102,7 @@ int64 MakeNodeWithParent(UserShare* share,
                          ModelType model_type,
                          const std::string& client_tag,
                          int64 parent_id) {
-  WriteTransaction trans(share);
+  WriteTransaction trans(FROM_HERE, share);
   ReadNode parent_node(&trans);
   EXPECT_TRUE(parent_node.InitByIdLookup(parent_id));
   WriteNode node(&trans);
@@ -117,7 +117,7 @@ int64 MakeFolderWithParent(UserShare* share,
                            ModelType model_type,
                            int64 parent_id,
                            BaseNode* predecessor) {
-  WriteTransaction trans(share);
+  WriteTransaction trans(FROM_HERE, share);
   ReadNode parent_node(&trans);
   EXPECT_TRUE(parent_node.InitByIdLookup(parent_id));
   WriteNode node(&trans);
@@ -135,7 +135,7 @@ int64 MakeServerNodeForType(UserShare* share,
   syncable::AddDefaultExtensionValue(model_type, &specifics);
   syncable::ScopedDirLookup dir(share->dir_manager.get(), share->name);
   EXPECT_TRUE(dir.good());
-  syncable::WriteTransaction trans(dir, syncable::UNITTEST, FROM_HERE);
+  syncable::WriteTransaction trans(FROM_HERE, syncable::UNITTEST, dir);
   // Attempt to lookup by nigori tag.
   std::string type_tag = syncable::ModelTypeToRootTag(model_type);
   syncable::Id node_id = syncable::Id::CreateFromServerId(type_tag);
@@ -174,16 +174,16 @@ class SyncApiTest : public testing::Test {
 
 TEST_F(SyncApiTest, SanityCheckTest) {
   {
-    ReadTransaction trans(test_user_share_.user_share());
+    ReadTransaction trans(FROM_HERE, test_user_share_.user_share());
     EXPECT_TRUE(trans.GetWrappedTrans() != NULL);
   }
   {
-    WriteTransaction trans(test_user_share_.user_share());
+    WriteTransaction trans(FROM_HERE, test_user_share_.user_share());
     EXPECT_TRUE(trans.GetWrappedTrans() != NULL);
   }
   {
     // No entries but root should exist
-    ReadTransaction trans(test_user_share_.user_share());
+    ReadTransaction trans(FROM_HERE, test_user_share_.user_share());
     ReadNode node(&trans);
     // Metahandle 1 can be root, sanity check 2
     EXPECT_FALSE(node.InitByIdLookup(2));
@@ -192,7 +192,7 @@ TEST_F(SyncApiTest, SanityCheckTest) {
 
 TEST_F(SyncApiTest, BasicTagWrite) {
   {
-    ReadTransaction trans(test_user_share_.user_share());
+    ReadTransaction trans(FROM_HERE, test_user_share_.user_share());
     ReadNode root_node(&trans);
     root_node.InitByRootLookup();
     EXPECT_EQ(root_node.GetFirstChildId(), 0);
@@ -202,7 +202,7 @@ TEST_F(SyncApiTest, BasicTagWrite) {
                          syncable::BOOKMARKS, "testtag"));
 
   {
-    ReadTransaction trans(test_user_share_.user_share());
+    ReadTransaction trans(FROM_HERE, test_user_share_.user_share());
     ReadNode node(&trans);
     EXPECT_TRUE(node.InitByClientTagLookup(syncable::BOOKMARKS,
         "testtag"));
@@ -232,7 +232,7 @@ TEST_F(SyncApiTest, GenerateSyncableHash) {
 
 TEST_F(SyncApiTest, ModelTypesSiloed) {
   {
-    WriteTransaction trans(test_user_share_.user_share());
+    WriteTransaction trans(FROM_HERE, test_user_share_.user_share());
     ReadNode root_node(&trans);
     root_node.InitByRootLookup();
     EXPECT_EQ(root_node.GetFirstChildId(), 0);
@@ -246,7 +246,7 @@ TEST_F(SyncApiTest, ModelTypesSiloed) {
                          syncable::AUTOFILL, "collideme"));
 
   {
-    ReadTransaction trans(test_user_share_.user_share());
+    ReadTransaction trans(FROM_HERE, test_user_share_.user_share());
 
     ReadNode bookmarknode(&trans);
     EXPECT_TRUE(bookmarknode.InitByClientTagLookup(syncable::BOOKMARKS,
@@ -268,13 +268,13 @@ TEST_F(SyncApiTest, ModelTypesSiloed) {
 
 TEST_F(SyncApiTest, ReadMissingTagsFails) {
   {
-    ReadTransaction trans(test_user_share_.user_share());
+    ReadTransaction trans(FROM_HERE, test_user_share_.user_share());
     ReadNode node(&trans);
     EXPECT_FALSE(node.InitByClientTagLookup(syncable::BOOKMARKS,
         "testtag"));
   }
   {
-    WriteTransaction trans(test_user_share_.user_share());
+    WriteTransaction trans(FROM_HERE, test_user_share_.user_share());
     WriteNode node(&trans);
     EXPECT_FALSE(node.InitByClientTagLookup(syncable::BOOKMARKS,
         "testtag"));
@@ -289,7 +289,7 @@ TEST_F(SyncApiTest, TestDeleteBehavior) {
   std::wstring test_title(L"test1");
 
   {
-    WriteTransaction trans(test_user_share_.user_share());
+    WriteTransaction trans(FROM_HERE, test_user_share_.user_share());
     ReadNode root_node(&trans);
     root_node.InitByRootLookup();
 
@@ -310,7 +310,7 @@ TEST_F(SyncApiTest, TestDeleteBehavior) {
 
   // Ensure we can delete something with a tag.
   {
-    WriteTransaction trans(test_user_share_.user_share());
+    WriteTransaction trans(FROM_HERE, test_user_share_.user_share());
     WriteNode wnode(&trans);
     EXPECT_TRUE(wnode.InitByClientTagLookup(syncable::BOOKMARKS,
         "testtag"));
@@ -323,7 +323,7 @@ TEST_F(SyncApiTest, TestDeleteBehavior) {
   // Lookup of a node which was deleted should return failure,
   // but have found some data about the node.
   {
-    ReadTransaction trans(test_user_share_.user_share());
+    ReadTransaction trans(FROM_HERE, test_user_share_.user_share());
     ReadNode node(&trans);
     EXPECT_FALSE(node.InitByClientTagLookup(syncable::BOOKMARKS,
         "testtag"));
@@ -333,7 +333,7 @@ TEST_F(SyncApiTest, TestDeleteBehavior) {
   }
 
   {
-    WriteTransaction trans(test_user_share_.user_share());
+    WriteTransaction trans(FROM_HERE, test_user_share_.user_share());
     ReadNode folder_node(&trans);
     EXPECT_TRUE(folder_node.InitByIdLookup(folder_id));
 
@@ -350,7 +350,7 @@ TEST_F(SyncApiTest, TestDeleteBehavior) {
 
   // Now look up should work.
   {
-    ReadTransaction trans(test_user_share_.user_share());
+    ReadTransaction trans(FROM_HERE, test_user_share_.user_share());
     ReadNode node(&trans);
     EXPECT_TRUE(node.InitByClientTagLookup(syncable::BOOKMARKS,
         "testtag"));
@@ -362,11 +362,11 @@ TEST_F(SyncApiTest, TestDeleteBehavior) {
 TEST_F(SyncApiTest, WriteAndReadPassword) {
   KeyParams params = {"localhost", "username", "passphrase"};
   {
-    ReadTransaction trans(test_user_share_.user_share());
+    ReadTransaction trans(FROM_HERE, test_user_share_.user_share());
     trans.GetCryptographer()->AddKey(params);
   }
   {
-    WriteTransaction trans(test_user_share_.user_share());
+    WriteTransaction trans(FROM_HERE, test_user_share_.user_share());
     ReadNode root_node(&trans);
     root_node.InitByRootLookup();
 
@@ -378,7 +378,7 @@ TEST_F(SyncApiTest, WriteAndReadPassword) {
     password_node.SetPasswordSpecifics(data);
   }
   {
-    ReadTransaction trans(test_user_share_.user_share());
+    ReadTransaction trans(FROM_HERE, test_user_share_.user_share());
     ReadNode root_node(&trans);
     root_node.InitByRootLookup();
 
@@ -394,7 +394,7 @@ TEST_F(SyncApiTest, WriteAndReadPassword) {
 TEST_F(SyncApiTest, BaseNodeSetSpecifics) {
   int64 child_id = MakeNode(test_user_share_.user_share(),
                             syncable::BOOKMARKS, "testtag");
-  WriteTransaction trans(test_user_share_.user_share());
+  WriteTransaction trans(FROM_HERE, test_user_share_.user_share());
   WriteNode node(&trans);
   EXPECT_TRUE(node.InitByIdLookup(child_id));
 
@@ -412,7 +412,7 @@ TEST_F(SyncApiTest, BaseNodeSetSpecifics) {
 TEST_F(SyncApiTest, BaseNodeSetSpecificsPreservesUnknownFields) {
   int64 child_id = MakeNode(test_user_share_.user_share(),
                             syncable::BOOKMARKS, "testtag");
-  WriteTransaction trans(test_user_share_.user_share());
+  WriteTransaction trans(FROM_HERE, test_user_share_.user_share());
   WriteNode node(&trans);
   EXPECT_TRUE(node.InitByIdLookup(child_id));
   EXPECT_TRUE(node.GetEntitySpecifics().unknown_fields().empty());
@@ -478,7 +478,7 @@ void CheckNodeValue(const BaseNode& node, const DictionaryValue& value,
 }  // namespace
 
 TEST_F(SyncApiTest, BaseNodeGetSummaryAsValue) {
-  ReadTransaction trans(test_user_share_.user_share());
+  ReadTransaction trans(FROM_HERE, test_user_share_.user_share());
   ReadNode node(&trans);
   node.InitByRootLookup();
   scoped_ptr<DictionaryValue> details(node.GetSummaryAsValue());
@@ -490,7 +490,7 @@ TEST_F(SyncApiTest, BaseNodeGetSummaryAsValue) {
 }
 
 TEST_F(SyncApiTest, BaseNodeGetDetailsAsValue) {
-  ReadTransaction trans(test_user_share_.user_share());
+  ReadTransaction trans(FROM_HERE, test_user_share_.user_share());
   ReadNode node(&trans);
   node.InitByRootLookup();
   scoped_ptr<DictionaryValue> details(node.GetDetailsAsValue());
@@ -574,7 +574,7 @@ TEST_F(SyncApiTest, ChangeRecordToValue) {
                             syncable::BOOKMARKS, "testtag");
   sync_pb::EntitySpecifics child_specifics;
   {
-    ReadTransaction trans(test_user_share_.user_share());
+    ReadTransaction trans(FROM_HERE, test_user_share_.user_share());
     ReadNode node(&trans);
     EXPECT_TRUE(node.InitByIdLookup(child_id));
     child_specifics = node.GetEntry()->Get(syncable::SPECIFICS);
@@ -582,7 +582,7 @@ TEST_F(SyncApiTest, ChangeRecordToValue) {
 
   // Add
   {
-    ReadTransaction trans(test_user_share_.user_share());
+    ReadTransaction trans(FROM_HERE, test_user_share_.user_share());
     SyncManager::ChangeRecord record;
     record.action = SyncManager::ChangeRecord::ACTION_ADD;
     record.id = 1;
@@ -594,7 +594,7 @@ TEST_F(SyncApiTest, ChangeRecordToValue) {
 
   // Update
   {
-    ReadTransaction trans(test_user_share_.user_share());
+    ReadTransaction trans(FROM_HERE, test_user_share_.user_share());
     SyncManager::ChangeRecord record;
     record.action = SyncManager::ChangeRecord::ACTION_UPDATE;
     record.id = child_id;
@@ -606,7 +606,7 @@ TEST_F(SyncApiTest, ChangeRecordToValue) {
 
   // Delete (no extra)
   {
-    ReadTransaction trans(test_user_share_.user_share());
+    ReadTransaction trans(FROM_HERE, test_user_share_.user_share());
     SyncManager::ChangeRecord record;
     record.action = SyncManager::ChangeRecord::ACTION_DELETE;
     record.id = child_id + 1;
@@ -617,7 +617,7 @@ TEST_F(SyncApiTest, ChangeRecordToValue) {
 
   // Delete (with extra)
   {
-    ReadTransaction trans(test_user_share_.user_share());
+    ReadTransaction trans(FROM_HERE, test_user_share_.user_share());
     SyncManager::ChangeRecord record;
     record.action = SyncManager::ChangeRecord::ACTION_DELETE;
     record.id = child_id + 1;
@@ -773,7 +773,7 @@ class SyncManagerTest : public testing::Test,
       return false;
 
     // Set the nigori cryptographer information.
-    WriteTransaction trans(share);
+    WriteTransaction trans(FROM_HERE, share);
     Cryptographer* cryptographer = trans.GetCryptographer();
     if (!cryptographer)
       return false;
@@ -926,7 +926,7 @@ TEST_F(SyncManagerTest, ProcessMessageGetRootNodeDetails) {
   DictionaryValue* node_info = NULL;
   EXPECT_TRUE(return_args.Get().GetDictionary(0, &node_info));
   if (node_info) {
-    ReadTransaction trans(sync_manager_.GetUserShare());
+    ReadTransaction trans(FROM_HERE, sync_manager_.GetUserShare());
     ReadNode node(&trans);
     node.InitByRootLookup();
     CheckNodeValue(node, *node_info, true);
@@ -949,7 +949,7 @@ void CheckGetNodesByIdReturnArgs(const SyncManager& sync_manager,
   DictionaryValue* node_info = NULL;
   EXPECT_TRUE(nodes->GetDictionary(0, &node_info));
   ASSERT_TRUE(node_info);
-  ReadTransaction trans(sync_manager.GetUserShare());
+  ReadTransaction trans(FROM_HERE, sync_manager.GetUserShare());
   ReadNode node(&trans);
   EXPECT_TRUE(node.InitByIdLookup(id));
   CheckNodeValue(node, *node_info, is_detailed);
@@ -962,7 +962,7 @@ class SyncManagerGetNodesByIdTest : public SyncManagerTest {
   void RunGetNodesByIdTest(const char* message_name, bool is_detailed) {
     int64 root_id = kInvalidId;
     {
-      ReadTransaction trans(sync_manager_.GetUserShare());
+      ReadTransaction trans(FROM_HERE, sync_manager_.GetUserShare());
       ReadNode root_node(&trans);
       root_node.InitByRootLookup();
       root_id = root_node.GetId();
@@ -1275,7 +1275,7 @@ TEST_F(SyncManagerTest, EncryptDataTypesWithNoData) {
   EXPECT_CALL(observer_, OnEncryptionComplete(expected_types));
   sync_manager_.EncryptDataTypes(encrypted_types);
   {
-    ReadTransaction trans(sync_manager_.GetUserShare());
+    ReadTransaction trans(FROM_HERE, sync_manager_.GetUserShare());
     EXPECT_EQ(expected_types,
               GetEncryptedTypes(&trans));
   }
@@ -1310,7 +1310,7 @@ TEST_F(SyncManagerTest, EncryptDataTypesWithData) {
   }
 
   {
-    ReadTransaction trans(sync_manager_.GetUserShare());
+    ReadTransaction trans(FROM_HERE, sync_manager_.GetUserShare());
     EXPECT_TRUE(syncable::VerifyDataTypeEncryption(trans.GetWrappedTrans(),
                                                    syncable::BOOKMARKS,
                                                    false /* not encrypted */));
@@ -1330,7 +1330,7 @@ TEST_F(SyncManagerTest, EncryptDataTypesWithData) {
   sync_manager_.EncryptDataTypes(encrypted_types);
 
   {
-    ReadTransaction trans(sync_manager_.GetUserShare());
+    ReadTransaction trans(FROM_HERE, sync_manager_.GetUserShare());
     EXPECT_EQ(encrypted_types,
               GetEncryptedTypes(&trans));
     EXPECT_TRUE(syncable::VerifyDataTypeEncryption(trans.GetWrappedTrans(),
@@ -1348,7 +1348,7 @@ TEST_F(SyncManagerTest, EncryptDataTypesWithData) {
 TEST_F(SyncManagerTest, SetPassphraseWithPassword) {
   EXPECT_TRUE(SetUpEncryption());
   {
-    WriteTransaction trans(sync_manager_.GetUserShare());
+    WriteTransaction trans(FROM_HERE, sync_manager_.GetUserShare());
     ReadNode root_node(&trans);
     root_node.InitByRootLookup();
 
@@ -1363,7 +1363,7 @@ TEST_F(SyncManagerTest, SetPassphraseWithPassword) {
   EXPECT_CALL(observer_, OnEncryptionComplete(_));
   sync_manager_.SetPassphrase("new_passphrase", true);
   {
-    ReadTransaction trans(sync_manager_.GetUserShare());
+    ReadTransaction trans(FROM_HERE, sync_manager_.GetUserShare());
     ReadNode root_node(&trans);
     root_node.InitByRootLookup();
 
@@ -1381,7 +1381,7 @@ TEST_F(SyncManagerTest, SetPassphraseWithEmptyPasswordNode) {
   int64 node_id = 0;
   std::string tag = "foo";
   {
-    WriteTransaction trans(sync_manager_.GetUserShare());
+    WriteTransaction trans(FROM_HERE, sync_manager_.GetUserShare());
     ReadNode root_node(&trans);
     root_node.InitByRootLookup();
 
@@ -1394,7 +1394,7 @@ TEST_F(SyncManagerTest, SetPassphraseWithEmptyPasswordNode) {
   EXPECT_CALL(observer_, OnEncryptionComplete(_));
   sync_manager_.SetPassphrase("new_passphrase", true);
   {
-    ReadTransaction trans(sync_manager_.GetUserShare());
+    ReadTransaction trans(FROM_HERE, sync_manager_.GetUserShare());
     ReadNode root_node(&trans);
     root_node.InitByRootLookup();
 
@@ -1403,7 +1403,7 @@ TEST_F(SyncManagerTest, SetPassphraseWithEmptyPasswordNode) {
                                                      tag));
   }
   {
-    ReadTransaction trans(sync_manager_.GetUserShare());
+    ReadTransaction trans(FROM_HERE, sync_manager_.GetUserShare());
     ReadNode root_node(&trans);
     root_node.InitByRootLookup();
 
diff --git a/chrome/browser/sync/engine/syncer.cc b/chrome/browser/sync/engine/syncer.cc
index d6a580d..abcf5f0 100644
--- a/chrome/browser/sync/engine/syncer.cc
+++ b/chrome/browser/sync/engine/syncer.cc
@@ -168,7 +168,7 @@ void Syncer::SyncShare(sessions::SyncSession* session,
           LOG(ERROR) << "Scoped dir lookup failed!";
           return;
         }
-        WriteTransaction trans(dir, SYNCER, FROM_HERE);
+        WriteTransaction trans(FROM_HERE, SYNCER, dir);
         sessions::ScopedSetSessionWriteTransaction set_trans(session, &trans);
 
         VLOG(1) << "Getting the Commit IDs";
diff --git a/chrome/browser/sync/engine/syncer_unittest.cc b/chrome/browser/sync/engine/syncer_unittest.cc
index 5fceff0..16c4783 100644
--- a/chrome/browser/sync/engine/syncer_unittest.cc
+++ b/chrome/browser/sync/engine/syncer_unittest.cc
@@ -197,7 +197,7 @@ class SyncerTest : public testing::Test,
 
     ScopedDirLookup dir(syncdb_.manager(), syncdb_.name());
     CHECK(dir.good());
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     syncable::Directory::ChildHandles children;
     dir->GetChildHandlesById(&trans, trans.root_id(), &children);
     ASSERT_TRUE(0 == children.size());
@@ -282,7 +282,7 @@ class SyncerTest : public testing::Test,
 
     map<int, syncable::Id> expected_positions;
     {  // Transaction scope.
-      WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+      WriteTransaction trans(FROM_HERE, UNITTEST, dir);
       while (!test->id.IsRoot()) {
         if (test->commit_index >= 0) {
           map<int, syncable::Id>::value_type entry(test->commit_index,
@@ -348,7 +348,7 @@ class SyncerTest : public testing::Test,
     // The expected order is "x", "b", "c", "e", truncated appropriately.
     for (size_t limit = expected_id_order.size() + 2; limit > 0; --limit) {
       StatusController* status = session_->status_controller();
-      WriteTransaction wtrans(dir, UNITTEST, FROM_HERE);
+      WriteTransaction wtrans(FROM_HERE, UNITTEST, dir);
       ScopedSetSessionWriteTransaction set_trans(session_.get(), &wtrans);
       status->set_unsynced_handles(unsynced_handle_view);
 
@@ -389,7 +389,7 @@ class SyncerTest : public testing::Test,
       const syncable::Id& id) {
     ScopedDirLookup dir(syncdb_.manager(), syncdb_.name());
     EXPECT_TRUE(dir.good());
-    WriteTransaction wtrans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction wtrans(FROM_HERE, UNITTEST, dir);
     MutableEntry entry(&wtrans, syncable::CREATE, wtrans.root_id(),
                        entry_name);
     EXPECT_TRUE(entry.good());
@@ -416,7 +416,7 @@ class SyncerTest : public testing::Test,
       ValueType default_value) const {
     ScopedDirLookup dir(syncdb_.manager(), syncdb_.name());
     EXPECT_TRUE(dir.good());
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry entry(&trans, GET_BY_HANDLE, metahandle);
     EXPECT_TRUE(entry.good());
     if (!entry.good()) {
@@ -489,7 +489,7 @@ TEST_F(SyncerTest, TestCallGatherUnsyncedEntries) {
   {
     Syncer::UnsyncedMetaHandles handles;
     {
-      ReadTransaction trans(dir, FROM_HERE);
+      ReadTransaction trans(FROM_HERE, dir);
       SyncerUtil::GetUnsyncedEntries(&trans, &handles);
     }
     ASSERT_TRUE(0 == handles.size());
@@ -508,7 +508,7 @@ TEST_F(SyncerTest, GetCommitIdsCommandTruncates) {
   int64 handle_d = CreateUnsyncedDirectory("D", ids_.MakeLocal("d"));
   int64 handle_e = CreateUnsyncedDirectory("E", ids_.MakeLocal("e"));
   {
-    WriteTransaction wtrans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction wtrans(FROM_HERE, UNITTEST, dir);
     MutableEntry entry_x(&wtrans, GET_BY_HANDLE, handle_x);
     MutableEntry entry_b(&wtrans, GET_BY_HANDLE, handle_b);
     MutableEntry entry_c(&wtrans, GET_BY_HANDLE, handle_c);
@@ -546,7 +546,7 @@ TEST_F(SyncerTest, TestCommitMetahandleIterator) {
   const vector<int64>& unsynced(status->unsynced_handles());
 
   {
-    WriteTransaction wtrans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction wtrans(FROM_HERE, UNITTEST, dir);
     ScopedSetSessionWriteTransaction set_trans(session_.get(), &wtrans);
 
     sessions::OrderedCommitSet commit_set(session_->routing_info());
@@ -563,7 +563,7 @@ TEST_F(SyncerTest, TestCommitMetahandleIterator) {
     session_metahandles.push_back(CreateUnsyncedDirectory("test3", "testid3"));
     status->set_unsynced_handles(session_metahandles);
 
-    WriteTransaction wtrans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction wtrans(FROM_HERE, UNITTEST, dir);
     ScopedSetSessionWriteTransaction set_trans(session_.get(), &wtrans);
     sessions::OrderedCommitSet commit_set(session_->routing_info());
     GetCommitIdsCommand::CommitMetahandleIterator iterator(unsynced, &wtrans,
@@ -589,7 +589,7 @@ TEST_F(SyncerTest, TestGetUnsyncedAndSimpleCommit) {
   ScopedDirLookup dir(syncdb_.manager(), syncdb_.name());
   ASSERT_TRUE(dir.good());
   {
-    WriteTransaction wtrans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction wtrans(FROM_HERE, UNITTEST, dir);
     MutableEntry parent(&wtrans, syncable::CREATE, wtrans.root_id(),
                         "Pete");
     ASSERT_TRUE(parent.good());
@@ -613,7 +613,7 @@ TEST_F(SyncerTest, TestGetUnsyncedAndSimpleCommit) {
   EXPECT_TRUE(parent_id_ == mock_server_->committed_ids()[0]);
   EXPECT_TRUE(child_id_ == mock_server_->committed_ids()[1]);
   {
-    ReadTransaction rt(dir, FROM_HERE);
+    ReadTransaction rt(FROM_HERE, dir);
     Entry entry(&rt, syncable::GET_BY_ID, child_id_);
     ASSERT_TRUE(entry.good());
     VerifyTestDataInEntry(&rt, &entry);
@@ -626,7 +626,7 @@ TEST_F(SyncerTest, TestPurgeWhileUnsynced) {
   ASSERT_TRUE(dir.good());
   syncable::Id pref_node_id = TestIdFactory::MakeServer("Tim");
   {
-    WriteTransaction wtrans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction wtrans(FROM_HERE, UNITTEST, dir);
     MutableEntry parent(&wtrans, syncable::CREATE, wtrans.root_id(), "Pete");
     ASSERT_TRUE(parent.good());
     parent.Put(syncable::IS_UNSYNCED, true);
@@ -661,14 +661,14 @@ TEST_F(SyncerTest, TestPurgeWhileUnsynced) {
   EXPECT_TRUE(parent_id_ == mock_server_->committed_ids()[0]);
   EXPECT_TRUE(child_id_ == mock_server_->committed_ids()[1]);
   {
-    ReadTransaction rt(dir, FROM_HERE);
+    ReadTransaction rt(FROM_HERE, dir);
     Entry entry(&rt, syncable::GET_BY_ID, child_id_);
     ASSERT_TRUE(entry.good());
     VerifyTestDataInEntry(&rt, &entry);
   }
   dir->SaveChanges();
   {
-    ReadTransaction rt(dir, FROM_HERE);
+    ReadTransaction rt(FROM_HERE, dir);
     Entry entry(&rt, syncable::GET_BY_ID, pref_node_id);
     ASSERT_FALSE(entry.good());
   }
@@ -679,7 +679,7 @@ TEST_F(SyncerTest, TestPurgeWhileUnapplied) {
   ScopedDirLookup dir(syncdb_.manager(), syncdb_.name());
   ASSERT_TRUE(dir.good());
   {
-    WriteTransaction wtrans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction wtrans(FROM_HERE, UNITTEST, dir);
     MutableEntry parent(&wtrans, syncable::CREATE, wtrans.root_id(), "Pete");
     ASSERT_TRUE(parent.good());
     parent.Put(syncable::IS_UNAPPLIED_UPDATE, true);
@@ -696,7 +696,7 @@ TEST_F(SyncerTest, TestPurgeWhileUnapplied) {
   syncer_->SyncShare(session_.get(), SYNCER_BEGIN, SYNCER_END);
   dir->SaveChanges();
   {
-    ReadTransaction rt(dir, FROM_HERE);
+    ReadTransaction rt(FROM_HERE, dir);
     Entry entry(&rt, syncable::GET_BY_ID, parent_id_);
     ASSERT_FALSE(entry.good());
   }
@@ -837,7 +837,7 @@ TEST_F(SyncerTest, TestCommitListOrderingWithNesting) {
   int64 now_minus_2h = ServerTimeToClientTime(now_server_time - 7200000);
 
   {
-    WriteTransaction wtrans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction wtrans(FROM_HERE, UNITTEST, dir);
     {
       MutableEntry parent(&wtrans, syncable::CREATE, wtrans.root_id(),
                           "Bob");
@@ -920,7 +920,7 @@ TEST_F(SyncerTest, TestCommitListOrderingWithNewItems) {
   ScopedDirLookup dir(syncdb_.manager(), syncdb_.name());
   ASSERT_TRUE(dir.good());
   {
-    WriteTransaction wtrans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction wtrans(FROM_HERE, UNITTEST, dir);
     MutableEntry parent(&wtrans, syncable::CREATE, wtrans.root_id(), "1");
     ASSERT_TRUE(parent.good());
     parent.Put(syncable::IS_UNSYNCED, true);
@@ -937,7 +937,7 @@ TEST_F(SyncerTest, TestCommitListOrderingWithNewItems) {
     child.Put(syncable::BASE_VERSION, 1);
   }
   {
-    WriteTransaction wtrans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction wtrans(FROM_HERE, UNITTEST, dir);
     MutableEntry parent(&wtrans, syncable::CREATE, parent_id_, "A");
     ASSERT_TRUE(parent.good());
     parent.Put(syncable::IS_UNSYNCED, true);
@@ -953,7 +953,7 @@ TEST_F(SyncerTest, TestCommitListOrderingWithNewItems) {
     parent.Put(syncable::BASE_VERSION, 1);
   }
   {
-    WriteTransaction wtrans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction wtrans(FROM_HERE, UNITTEST, dir);
     MutableEntry parent(&wtrans, syncable::CREATE, child_id_, "A");
     ASSERT_TRUE(parent.good());
     parent.Put(syncable::IS_UNSYNCED, true);
@@ -988,7 +988,7 @@ TEST_F(SyncerTest, TestCommitListOrderingCounterexample) {
   syncable::Id child2_id = ids_.NewServerId();
 
   {
-    WriteTransaction wtrans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction wtrans(FROM_HERE, UNITTEST, dir);
     MutableEntry parent(&wtrans, syncable::CREATE, wtrans.root_id(), "P");
     ASSERT_TRUE(parent.good());
     parent.Put(syncable::IS_UNSYNCED, true);
@@ -1029,7 +1029,7 @@ TEST_F(SyncerTest, TestCommitListOrderingAndNewParent) {
   string child_name = "B";
 
   {
-    WriteTransaction wtrans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction wtrans(FROM_HERE, UNITTEST, dir);
     MutableEntry parent(&wtrans, syncable::CREATE, wtrans.root_id(),
                         parent1_name);
     ASSERT_TRUE(parent.good());
@@ -1043,7 +1043,7 @@ TEST_F(SyncerTest, TestCommitListOrderingAndNewParent) {
   syncable::Id parent2_id = ids_.NewLocalId();
   syncable::Id child_id = ids_.NewServerId();
   {
-    WriteTransaction wtrans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction wtrans(FROM_HERE, UNITTEST, dir);
     MutableEntry parent2(&wtrans, syncable::CREATE, parent_id_, parent2_name);
     ASSERT_TRUE(parent2.good());
     parent2.Put(syncable::IS_UNSYNCED, true);
@@ -1068,7 +1068,7 @@ TEST_F(SyncerTest, TestCommitListOrderingAndNewParent) {
   EXPECT_TRUE(parent2_id == mock_server_->committed_ids()[1]);
   EXPECT_TRUE(child_id == mock_server_->committed_ids()[2]);
   {
-    ReadTransaction rtrans(dir, FROM_HERE);
+    ReadTransaction rtrans(FROM_HERE, dir);
     // Check that things committed correctly.
     Entry entry_1(&rtrans, syncable::GET_BY_ID, parent_id_);
     EXPECT_EQ(entry_1.Get(NON_UNIQUE_NAME), parent1_name);
@@ -1100,7 +1100,7 @@ TEST_F(SyncerTest, TestCommitListOrderingAndNewParentAndChild) {
   string child_name = "B";
 
   {
-    WriteTransaction wtrans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction wtrans(FROM_HERE, UNITTEST, dir);
     MutableEntry parent(&wtrans,
                         syncable::CREATE,
                         wtrans.root_id(),
@@ -1117,7 +1117,7 @@ TEST_F(SyncerTest, TestCommitListOrderingAndNewParentAndChild) {
   const Id parent2_local_id = ids_.NewLocalId();
   const Id child_local_id = ids_.NewLocalId();
   {
-    WriteTransaction wtrans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction wtrans(FROM_HERE, UNITTEST, dir);
     MutableEntry parent2(&wtrans, syncable::CREATE, parent_id_, parent2_name);
     ASSERT_TRUE(parent2.good());
     parent2.Put(syncable::IS_UNSYNCED, true);
@@ -1143,7 +1143,7 @@ TEST_F(SyncerTest, TestCommitListOrderingAndNewParentAndChild) {
   EXPECT_TRUE(parent2_local_id == mock_server_->committed_ids()[1]);
   EXPECT_TRUE(child_local_id == mock_server_->committed_ids()[2]);
   {
-    ReadTransaction rtrans(dir, FROM_HERE);
+    ReadTransaction rtrans(FROM_HERE, dir);
 
     Entry parent(&rtrans, syncable::GET_BY_ID,
                  GetOnlyEntryWithName(&rtrans, rtrans.root_id(), parent_name));
@@ -1206,7 +1206,7 @@ TEST_F(SyncerTest, TestBasicUpdate) {
 
   SyncShareAsDelegate();
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     Entry entry(&trans, GET_BY_ID,
                syncable::Id::CreateFromServerId("some_id"));
     ASSERT_TRUE(entry.good());
@@ -1265,7 +1265,7 @@ TEST_F(SyncerTest, IllegalAndLegalUpdates) {
   }
 
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     // Even though it has the same name, it should work.
     Entry name_clash(&trans, GET_BY_ID, ids_.FromNumber(2));
     ASSERT_TRUE(name_clash.good());
@@ -1302,7 +1302,7 @@ TEST_F(SyncerTest, IllegalAndLegalUpdates) {
   mock_server_->AddUpdateDirectory(4, 0, "old_version", 10, 10);
   syncer_->SyncShare(session_.get(), SYNCER_BEGIN, SYNCER_END);
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
 
     Entry still_a_dir(&trans, GET_BY_ID, ids_.FromNumber(10));
     ASSERT_TRUE(still_a_dir.good());
@@ -1366,7 +1366,7 @@ TEST_F(SyncerTest, CommitTimeRename) {
 
   // Create a folder and an entry.
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry parent(&trans, CREATE, root_id_, "Folder");
     ASSERT_TRUE(parent.good());
     parent.Put(IS_DIR, true);
@@ -1387,7 +1387,7 @@ TEST_F(SyncerTest, CommitTimeRename) {
 
   // Verify it was correctly renamed.
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry entry_folder(&trans, GET_BY_HANDLE, metahandle_folder);
     ASSERT_TRUE(entry_folder.good());
     EXPECT_EQ("renamed_Folder", entry_folder.Get(NON_UNIQUE_NAME));
@@ -1416,7 +1416,7 @@ TEST_F(SyncerTest, CommitTimeRenameI18N) {
   int64 metahandle;
   // Create a folder, expect a commit time rename.
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry parent(&trans, CREATE, root_id_, "Folder");
     ASSERT_TRUE(parent.good());
     parent.Put(IS_DIR, true);
@@ -1430,7 +1430,7 @@ TEST_F(SyncerTest, CommitTimeRenameI18N) {
 
   // Verify it was correctly renamed.
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     string expected_folder_name(i18nString);
     expected_folder_name.append("Folder");
 
@@ -1450,7 +1450,7 @@ TEST_F(SyncerTest, CommitReuniteUpdateAdjustsChildren) {
   // Create a folder in the root.
   int64 metahandle_folder;
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry entry(&trans, CREATE, trans.root_id(), "new_folder");
     ASSERT_TRUE(entry.good());
     entry.Put(IS_DIR, true);
@@ -1463,7 +1463,7 @@ TEST_F(SyncerTest, CommitReuniteUpdateAdjustsChildren) {
   syncable::Id folder_id;
   int64 metahandle_entry;
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry entry(&trans, GET_BY_HANDLE, metahandle_folder);
     ASSERT_TRUE(entry.good());
     folder_id = entry.Get(ID);
@@ -1472,7 +1472,7 @@ TEST_F(SyncerTest, CommitReuniteUpdateAdjustsChildren) {
 
   // Create an entry in the newly created folder.
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry entry(&trans, CREATE, folder_id, "new_entry");
     ASSERT_TRUE(entry.good());
     metahandle_entry = entry.Get(META_HANDLE);
@@ -1482,7 +1482,7 @@ TEST_F(SyncerTest, CommitReuniteUpdateAdjustsChildren) {
   // Verify it and pull the ID out of the entry.
   syncable::Id entry_id;
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry entry(&trans, syncable::GET_BY_HANDLE, metahandle_entry);
     ASSERT_TRUE(entry.good());
     EXPECT_EQ(folder_id, entry.Get(PARENT_ID));
@@ -1512,7 +1512,7 @@ TEST_F(SyncerTest, CommitReuniteUpdateAdjustsChildren) {
   SyncShareAsDelegate();
   {
     // The folder's ID should have been updated.
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry folder(&trans, GET_BY_HANDLE, metahandle_folder);
     ASSERT_TRUE(folder.good());
     EXPECT_EQ("new_folder", folder.Get(NON_UNIQUE_NAME));
@@ -1544,7 +1544,7 @@ TEST_F(SyncerTest, CommitReuniteUpdate) {
   // Create an entry in the root.
   int64 entry_metahandle;
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry entry(&trans, CREATE, trans.root_id(), "new_entry");
     ASSERT_TRUE(entry.good());
     entry_metahandle = entry.Get(META_HANDLE);
@@ -1554,7 +1554,7 @@ TEST_F(SyncerTest, CommitReuniteUpdate) {
   // Verify it and pull the ID out.
   syncable::Id entry_id;
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
 
     Entry entry(&trans, GET_BY_HANDLE, entry_metahandle);
     ASSERT_TRUE(entry.good());
@@ -1580,7 +1580,7 @@ TEST_F(SyncerTest, CommitReuniteUpdate) {
   // Alright! Apply that update!
   SyncShareAsDelegate();
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry entry(&trans, GET_BY_HANDLE, entry_metahandle);
     ASSERT_TRUE(entry.good());
     EXPECT_TRUE(new_version == entry.Get(BASE_VERSION));
@@ -1601,7 +1601,7 @@ TEST_F(SyncerTest, CommitReuniteUpdateDoesNotChokeOnDeletedLocalEntry) {
   // Create a entry in the root.
   int64 entry_metahandle;
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry entry(&trans, CREATE, trans.root_id(), "new_entry");
     ASSERT_TRUE(entry.good());
     entry_metahandle = entry.Get(META_HANDLE);
@@ -1610,7 +1610,7 @@ TEST_F(SyncerTest, CommitReuniteUpdateDoesNotChokeOnDeletedLocalEntry) {
   // Verify it and pull the ID out.
   syncable::Id entry_id;
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry entry(&trans, GET_BY_HANDLE, entry_metahandle);
     ASSERT_TRUE(entry.good());
     entry_id = entry.Get(ID);
@@ -1635,7 +1635,7 @@ TEST_F(SyncerTest, CommitReuniteUpdateDoesNotChokeOnDeletedLocalEntry) {
 
   // Purposefully delete the entry now before the update application finishes.
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     Id new_entry_id = GetOnlyEntryWithName(
         &trans, trans.root_id(), "new_entry");
     MutableEntry entry(&trans, GET_BY_ID, new_entry_id);
@@ -1646,7 +1646,7 @@ TEST_F(SyncerTest, CommitReuniteUpdateDoesNotChokeOnDeletedLocalEntry) {
   // Just don't CHECK fail in sync, have the update split.
   SyncShareAsDelegate();
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Id new_entry_id = GetOnlyEntryWithName(
         &trans, trans.root_id(), "new_entry");
     Entry entry(&trans, GET_BY_ID, new_entry_id);
@@ -1668,7 +1668,7 @@ TEST_F(SyncerTest, ConflictMatchingEntryHandlesUnsanitizedNames) {
   mock_server_->set_conflict_all_commits(true);
   SyncShareAsDelegate();
   {
-    WriteTransaction wtrans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction wtrans(FROM_HERE, UNITTEST, dir);
 
     MutableEntry A(&wtrans, GET_BY_ID, ids_.FromNumber(1));
     ASSERT_TRUE(A.good());
@@ -1686,7 +1686,7 @@ TEST_F(SyncerTest, ConflictMatchingEntryHandlesUnsanitizedNames) {
   mock_server_->set_conflict_all_commits(false);
 
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
 
     Entry A(&trans, GET_BY_ID, ids_.FromNumber(1));
     ASSERT_TRUE(A.good());
@@ -1710,7 +1710,7 @@ TEST_F(SyncerTest, ConflictMatchingEntryHandlesNormalNames) {
   mock_server_->set_conflict_all_commits(true);
   SyncShareAsDelegate();
   {
-    WriteTransaction wtrans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction wtrans(FROM_HERE, UNITTEST, dir);
 
     MutableEntry A(&wtrans, GET_BY_ID, ids_.FromNumber(1));
     ASSERT_TRUE(A.good());
@@ -1728,7 +1728,7 @@ TEST_F(SyncerTest, ConflictMatchingEntryHandlesNormalNames) {
   mock_server_->set_conflict_all_commits(false);
 
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
 
     Entry A(&trans, GET_BY_ID, ids_.FromNumber(1));
     ASSERT_TRUE(A.good());
@@ -1753,7 +1753,7 @@ TEST_F(SyncerTest, ReverseFolderOrderingTest) {
   mock_server_->AddUpdateDirectory(2, 1, "child", 10, 10);
   mock_server_->AddUpdateDirectory(1, 0, "parent", 10, 10);
   LoopSyncShare();
-  ReadTransaction trans(dir, FROM_HERE);
+  ReadTransaction trans(FROM_HERE, dir);
 
   Id child_id = GetOnlyEntryWithName(
         &trans, ids_.FromNumber(4), "gggchild");
@@ -1767,7 +1767,7 @@ class EntryCreatedInNewFolderTest : public SyncerTest {
     ScopedDirLookup dir(syncdb_.manager(), syncdb_.name());
     CHECK(dir.good());
 
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry bob(&trans,
                      syncable::GET_BY_ID,
                      GetOnlyEntryWithName(&trans,
@@ -1789,7 +1789,7 @@ TEST_F(EntryCreatedInNewFolderTest, EntryCreatedInNewFolderMidSync) {
   ASSERT_TRUE(dir.good());
   dir->set_store_birthday(mock_server_->store_birthday());
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry entry(&trans, syncable::CREATE, trans.root_id(),
                        "bob");
     ASSERT_TRUE(entry.good());
@@ -1804,7 +1804,7 @@ TEST_F(EntryCreatedInNewFolderTest, EntryCreatedInNewFolderMidSync) {
   syncer_->SyncShare(session_.get(), BUILD_COMMIT_REQUEST, SYNCER_END);
   EXPECT_TRUE(1 == mock_server_->committed_ids().size());
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry parent_entry(&trans, syncable::GET_BY_ID,
         GetOnlyEntryWithName(&trans, TestIdFactory::root(), "bob"));
     ASSERT_TRUE(parent_entry.good());
@@ -1832,7 +1832,7 @@ TEST_F(SyncerTest, UnappliedUpdateOnCreatedItemItemDoesNotCrash) {
   int64 metahandle_fred;
   {
     // Create an item.
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry fred_match(&trans, CREATE, trans.root_id(),
                             "fred_match");
     ASSERT_TRUE(fred_match.good());
@@ -1846,7 +1846,7 @@ TEST_F(SyncerTest, UnappliedUpdateOnCreatedItemItemDoesNotCrash) {
   syncable::Id fred_match_id;
   {
     // Now receive a change from outside.
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry fred_match(&trans, GET_BY_HANDLE, metahandle_fred);
     ASSERT_TRUE(fred_match.good());
     EXPECT_TRUE(fred_match.Get(ID).ServerKnows());
@@ -1870,7 +1870,7 @@ TEST_F(SyncerTest, DoublyChangedWithResolver) {
   ScopedDirLookup dir(syncdb_.manager(), syncdb_.name());
   CHECK(dir.good());
   {
-    WriteTransaction wtrans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction wtrans(FROM_HERE, UNITTEST, dir);
     MutableEntry parent(&wtrans, syncable::CREATE, root_id_, "Folder");
     ASSERT_TRUE(parent.good());
     parent.Put(syncable::IS_DIR, true);
@@ -1888,7 +1888,7 @@ TEST_F(SyncerTest, DoublyChangedWithResolver) {
   LoopSyncShare();
   syncable::Directory::ChildHandles children;
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     dir->GetChildHandlesById(&trans, parent_id_, &children);
     // We expect the conflict resolver to preserve the local entry.
     Entry child(&trans, syncable::GET_BY_ID, child_id_);
@@ -1913,7 +1913,7 @@ TEST_F(SyncerTest, CommitsUpdateDoesntAlterEntry) {
   int64 test_time = 123456;
   int64 entry_metahandle;
   {
-    WriteTransaction wtrans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction wtrans(FROM_HERE, UNITTEST, dir);
     MutableEntry entry(&wtrans, syncable::CREATE, root_id_, "Pete");
     ASSERT_TRUE(entry.good());
     EXPECT_FALSE(entry.Get(ID).ServerKnows());
@@ -1928,7 +1928,7 @@ TEST_F(SyncerTest, CommitsUpdateDoesntAlterEntry) {
   int64 version;
   int64 server_position_in_parent;
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry entry(&trans, syncable::GET_BY_HANDLE, entry_metahandle);
     ASSERT_TRUE(entry.good());
     id = entry.Get(ID);
@@ -1944,7 +1944,7 @@ TEST_F(SyncerTest, CommitsUpdateDoesntAlterEntry) {
   EXPECT_EQ(server_position_in_parent, update->position_in_parent());
   SyncShareAsDelegate();
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry entry(&trans, syncable::GET_BY_ID, id);
     ASSERT_TRUE(entry.good());
     EXPECT_TRUE(entry.Get(MTIME) == test_time);
@@ -1958,7 +1958,7 @@ TEST_F(SyncerTest, ParentAndChildBothMatch) {
   syncable::Id child_id = ids_.NewServerId();
 
   {
-    WriteTransaction wtrans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction wtrans(FROM_HERE, UNITTEST, dir);
     MutableEntry parent(&wtrans, CREATE, root_id_, "Folder");
     ASSERT_TRUE(parent.good());
     parent.Put(IS_DIR, true);
@@ -1981,7 +1981,7 @@ TEST_F(SyncerTest, ParentAndChildBothMatch) {
   SyncShareAsDelegate();
   SyncShareAsDelegate();
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Directory::ChildHandles children;
     dir->GetChildHandlesById(&trans, root_id_, &children);
     EXPECT_TRUE(1 == children.size());
@@ -2001,7 +2001,7 @@ TEST_F(SyncerTest, CommittingNewDeleted) {
   ScopedDirLookup dir(syncdb_.manager(), syncdb_.name());
   CHECK(dir.good());
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry entry(&trans, CREATE, trans.root_id(), "bob");
     entry.Put(IS_UNSYNCED, true);
     entry.Put(IS_DEL, true);
@@ -2024,7 +2024,7 @@ TEST_F(SyncerTest, UnappliedUpdateDuringCommit) {
   ScopedDirLookup dir(syncdb_.manager(), syncdb_.name());
   CHECK(dir.good());
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry entry(&trans, CREATE, trans.root_id(), "bob");
     entry.Put(ID, ids_.FromNumber(20));
     entry.Put(BASE_VERSION, 1);
@@ -2059,7 +2059,7 @@ TEST_F(SyncerTest, DeletingEntryInFolder) {
 
   int64 existing_metahandle;
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry entry(&trans, CREATE, trans.root_id(), "existing");
     ASSERT_TRUE(entry.good());
     entry.Put(IS_DIR, true);
@@ -2069,7 +2069,7 @@ TEST_F(SyncerTest, DeletingEntryInFolder) {
   }
   syncer_->SyncShare(session_.get(), SYNCER_BEGIN, SYNCER_END);
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry newfolder(&trans, CREATE, trans.root_id(), "new");
     ASSERT_TRUE(newfolder.good());
     newfolder.Put(IS_DIR, true);
@@ -2098,7 +2098,7 @@ TEST_F(SyncerTest, DeletingEntryWithLocalEdits) {
   mock_server_->AddUpdateDirectory(1, 0, "bob", 1, 10);
   SyncShareAsDelegate();
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry newfolder(&trans, CREATE, ids_.FromNumber(1), "local");
     ASSERT_TRUE(newfolder.good());
     newfolder.Put(IS_UNSYNCED, true);
@@ -2110,7 +2110,7 @@ TEST_F(SyncerTest, DeletingEntryWithLocalEdits) {
   mock_server_->SetLastUpdateDeleted();
   syncer_->SyncShare(session_.get(), SYNCER_BEGIN, APPLY_UPDATES);
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry entry(&trans, syncable::GET_BY_HANDLE, newfolder_metahandle);
     ASSERT_TRUE(entry.good());
   }
@@ -2126,7 +2126,7 @@ TEST_F(SyncerTest, FolderSwapUpdate) {
   mock_server_->AddUpdateDirectory(7801, 0, "fred", 2, 20);
   SyncShareAsDelegate();
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry id1(&trans, GET_BY_ID, ids_.FromNumber(7801));
     ASSERT_TRUE(id1.good());
     EXPECT_TRUE("fred" == id1.Get(NON_UNIQUE_NAME));
@@ -2147,7 +2147,7 @@ TEST_F(SyncerTest, NameCollidingFolderSwapWorksFine) {
   mock_server_->AddUpdateDirectory(4096, 0, "alice", 1, 10);
   SyncShareAsDelegate();
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry id1(&trans, GET_BY_ID, ids_.FromNumber(7801));
     ASSERT_TRUE(id1.good());
     EXPECT_TRUE("bob" == id1.Get(NON_UNIQUE_NAME));
@@ -2166,7 +2166,7 @@ TEST_F(SyncerTest, NameCollidingFolderSwapWorksFine) {
   mock_server_->AddUpdateDirectory(4096, 0, "bob", 2, 20);
   SyncShareAsDelegate();
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry id1(&trans, GET_BY_ID, ids_.FromNumber(7801));
     ASSERT_TRUE(id1.good());
     EXPECT_TRUE("fred" == id1.Get(NON_UNIQUE_NAME));
@@ -2189,7 +2189,7 @@ TEST_F(SyncerTest, CommitManyItemsInOneGo) {
   uint32 items_to_commit = kDefaultMaxCommitBatchSize * max_batches;
   CHECK(dir.good());
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     for (uint32 i = 0; i < items_to_commit; i++) {
       string nameutf8 = base::StringPrintf("%d", i);
       string name(nameutf8.begin(), nameutf8.end());
@@ -2219,7 +2219,7 @@ TEST_F(SyncerTest, HugeConflict) {
   // Create a lot of updates for which the parent does not exist yet.
   // Generate a huge deep tree which should all fail to apply at first.
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     for (int i = 0; i < item_count ; i++) {
       syncable::Id next_id = ids_.NewServerId();
       tree_ids.push_back(next_id);
@@ -2231,7 +2231,7 @@ TEST_F(SyncerTest, HugeConflict) {
 
   // Check they're in the expected conflict state.
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     for (int i = 0; i < item_count; i++) {
       Entry e(&trans, GET_BY_ID, tree_ids[i]);
       // They should all exist but none should be applied.
@@ -2248,7 +2248,7 @@ TEST_F(SyncerTest, HugeConflict) {
 
   // Now they should all be OK.
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     for (int i = 0; i < item_count; i++) {
       Entry e(&trans, GET_BY_ID, tree_ids[i]);
       ASSERT_TRUE(e.good());
@@ -2264,7 +2264,7 @@ TEST_F(SyncerTest, DontCrashOnCaseChange) {
   mock_server_->AddUpdateDirectory(1, 0, "bob", 1, 10);
   SyncShareAsDelegate();
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry e(&trans, GET_BY_ID, ids_.FromNumber(1));
     ASSERT_TRUE(e.good());
     e.Put(IS_UNSYNCED, true);
@@ -2294,7 +2294,7 @@ TEST_F(SyncerTest, NewEntryAndAlteredServerEntrySharePath) {
   int64 local_folder_handle;
   syncable::Id local_folder_id;
   {
-    WriteTransaction wtrans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction wtrans(FROM_HERE, UNITTEST, dir);
     MutableEntry new_entry(&wtrans, CREATE, wtrans.root_id(), "Bar.htm");
     ASSERT_TRUE(new_entry.good());
     local_folder_id = new_entry.Get(ID);
@@ -2311,7 +2311,7 @@ TEST_F(SyncerTest, NewEntryAndAlteredServerEntrySharePath) {
   saw_syncer_event_ = false;
   {
     // Update #20 should have been dropped in favor of the local version.
-    WriteTransaction wtrans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction wtrans(FROM_HERE, UNITTEST, dir);
     MutableEntry server(&wtrans, GET_BY_ID, ids_.FromNumber(1));
     MutableEntry local(&wtrans, GET_BY_HANDLE, local_folder_handle);
     ASSERT_TRUE(server.good());
@@ -2335,7 +2335,7 @@ TEST_F(SyncerTest, NewEntryAndAlteredServerEntrySharePath) {
   SyncShareAsDelegate();
   saw_syncer_event_ = false;
   {
-    WriteTransaction wtrans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction wtrans(FROM_HERE, UNITTEST, dir);
     MutableEntry server(&wtrans, GET_BY_ID, ids_.FromNumber(1));
     MutableEntry local(&wtrans, GET_BY_HANDLE, local_folder_handle);
     ASSERT_TRUE(server.good());
@@ -2362,7 +2362,7 @@ TEST_F(SyncerTest, NewEntryAndAlteredServerEntrySharePath_OldBookmarksProto) {
   int64 local_folder_handle;
   syncable::Id local_folder_id;
   {
-    WriteTransaction wtrans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction wtrans(FROM_HERE, UNITTEST, dir);
     MutableEntry new_entry(&wtrans, CREATE, wtrans.root_id(), "Bar.htm");
     ASSERT_TRUE(new_entry.good());
     local_folder_id = new_entry.Get(ID);
@@ -2379,7 +2379,7 @@ TEST_F(SyncerTest, NewEntryAndAlteredServerEntrySharePath_OldBookmarksProto) {
   saw_syncer_event_ = false;
   {
     // Update #20 should have been dropped in favor of the local version.
-    WriteTransaction wtrans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction wtrans(FROM_HERE, UNITTEST, dir);
     MutableEntry server(&wtrans, GET_BY_ID, ids_.FromNumber(1));
     MutableEntry local(&wtrans, GET_BY_HANDLE, local_folder_handle);
     ASSERT_TRUE(server.good());
@@ -2403,7 +2403,7 @@ TEST_F(SyncerTest, NewEntryAndAlteredServerEntrySharePath_OldBookmarksProto) {
   SyncShareAsDelegate();
   saw_syncer_event_ = false;
   {
-    WriteTransaction wtrans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction wtrans(FROM_HERE, UNITTEST, dir);
     MutableEntry server(&wtrans, GET_BY_ID, ids_.FromNumber(1));
     MutableEntry local(&wtrans, GET_BY_HANDLE, local_folder_handle);
     ASSERT_TRUE(server.good());
@@ -2430,7 +2430,7 @@ TEST_F(SyncerTest, SiblingDirectoriesBecomeCircular) {
   mock_server_->AddUpdateDirectory(2, 0, "B", 10, 10);
   SyncShareAsDelegate();
   {
-    WriteTransaction wtrans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction wtrans(FROM_HERE, UNITTEST, dir);
     MutableEntry A(&wtrans, GET_BY_ID, ids_.FromNumber(1));
     ASSERT_TRUE(A.good());
     A.Put(IS_UNSYNCED, true);
@@ -2442,7 +2442,7 @@ TEST_F(SyncerTest, SiblingDirectoriesBecomeCircular) {
   SyncShareAsDelegate();
   saw_syncer_event_ = false;
   {
-    WriteTransaction wtrans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction wtrans(FROM_HERE, UNITTEST, dir);
     MutableEntry A(&wtrans, GET_BY_ID, ids_.FromNumber(1));
     ASSERT_TRUE(A.good());
     MutableEntry B(&wtrans, GET_BY_ID, ids_.FromNumber(2));
@@ -2462,7 +2462,7 @@ TEST_F(SyncerTest, ConflictSetClassificationError) {
   mock_server_->set_conflict_all_commits(true);
   SyncShareAsDelegate();
   {
-    WriteTransaction wtrans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction wtrans(FROM_HERE, UNITTEST, dir);
     MutableEntry A(&wtrans, GET_BY_ID, ids_.FromNumber(1));
     ASSERT_TRUE(A.good());
     A.Put(IS_UNSYNCED, true);
@@ -2486,7 +2486,7 @@ TEST_F(SyncerTest, SwapEntryNames) {
   mock_server_->set_conflict_all_commits(true);
   SyncShareAsDelegate();
   {
-    WriteTransaction wtrans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction wtrans(FROM_HERE, UNITTEST, dir);
     MutableEntry A(&wtrans, GET_BY_ID, ids_.FromNumber(1));
     ASSERT_TRUE(A.good());
     A.Put(IS_UNSYNCED, true);
@@ -2509,7 +2509,7 @@ TEST_F(SyncerTest, DualDeletionWithNewItemNameClash) {
   mock_server_->set_conflict_all_commits(true);
   SyncShareAsDelegate();
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry B(&trans, GET_BY_ID, ids_.FromNumber(2));
     ASSERT_TRUE(B.good());
     WriteTestDataToEntry(&trans, &B);
@@ -2519,7 +2519,7 @@ TEST_F(SyncerTest, DualDeletionWithNewItemNameClash) {
   mock_server_->SetLastUpdateDeleted();
   SyncShareAsDelegate();
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry B(&trans, GET_BY_ID, ids_.FromNumber(2));
     ASSERT_TRUE(B.good());
     EXPECT_FALSE(B.Get(IS_UNSYNCED));
@@ -2535,7 +2535,7 @@ TEST_F(SyncerTest, FixDirectoryLoopConflict) {
   mock_server_->AddUpdateDirectory(2, 0, "fred", 1, 10);
   SyncShareAsDelegate();
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry bob(&trans, GET_BY_ID, ids_.FromNumber(1));
     ASSERT_TRUE(bob.good());
     bob.Put(IS_UNSYNCED, true);
@@ -2546,7 +2546,7 @@ TEST_F(SyncerTest, FixDirectoryLoopConflict) {
   SyncShareAsDelegate();
   SyncShareAsDelegate();
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry bob(&trans, GET_BY_ID, ids_.FromNumber(1));
     ASSERT_TRUE(bob.good());
     Entry fred(&trans, GET_BY_ID, ids_.FromNumber(2));
@@ -2568,7 +2568,7 @@ TEST_F(SyncerTest, ResolveWeWroteTheyDeleted) {
   mock_server_->AddUpdateBookmark(1, 0, "bob", 1, 10);
   SyncShareAsDelegate();
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry bob(&trans, GET_BY_ID, ids_.FromNumber(1));
     ASSERT_TRUE(bob.good());
     bob_metahandle = bob.Get(META_HANDLE);
@@ -2580,7 +2580,7 @@ TEST_F(SyncerTest, ResolveWeWroteTheyDeleted) {
   SyncShareAsDelegate();
   SyncShareAsDelegate();
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry bob(&trans, GET_BY_HANDLE, bob_metahandle);
     ASSERT_TRUE(bob.good());
     EXPECT_TRUE(bob.Get(IS_UNSYNCED));
@@ -2604,7 +2604,7 @@ TEST_F(SyncerTest, ServerDeletingFolderWeHaveMovedSomethingInto) {
       "fred", 1, 10);
   SyncShareAsDelegate();
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry bob(&trans, GET_BY_ID, bob_id);
     ASSERT_TRUE(bob.good());
     bob.Put(IS_UNSYNCED, true);
@@ -2617,7 +2617,7 @@ TEST_F(SyncerTest, ServerDeletingFolderWeHaveMovedSomethingInto) {
   SyncShareAsDelegate();
   SyncShareAsDelegate();
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
 
     Entry bob(&trans, GET_BY_ID, bob_id);
     ASSERT_TRUE(bob.good());
@@ -2653,7 +2653,7 @@ TEST_F(SyncerTest, DISABLED_ServerDeletingFolderWeHaveAnOpenEntryIn) {
   mock_server_->AddUpdateDirectory(2, 0, "fred", 1, 10);
   SyncShareAsDelegate();
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry bob(&trans, GET_BY_ID, ids_.FromNumber(1));
     ASSERT_TRUE(bob.good());
     bob.Put(IS_UNSYNCED, true);
@@ -2661,7 +2661,7 @@ TEST_F(SyncerTest, DISABLED_ServerDeletingFolderWeHaveAnOpenEntryIn) {
   }
   SyncShareAsDelegate();
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry bob(&trans, GET_BY_ID, ids_.FromNumber(1));
     ASSERT_TRUE(bob.good());
     EXPECT_FALSE(bob.Get(IS_UNSYNCED));
@@ -2683,7 +2683,7 @@ TEST_F(SyncerTest, DISABLED_ServerDeletingFolderWeHaveAnOpenEntryIn) {
   SyncShareAsDelegate();
   EXPECT_FALSE(saw_syncer_event_);
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry bob(&trans, GET_BY_ID, ids_.FromNumber(1));
     ASSERT_TRUE(bob.good());
     Id fred_id =
@@ -2711,7 +2711,7 @@ TEST_F(SyncerTest, WeMovedSomethingIntoAFolderServerHasDeleted) {
       "fred", 1, 10);
   SyncShareAsDelegate();
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     Entry fred(&trans, GET_BY_ID, fred_id);
     ASSERT_TRUE(fred.good());
 
@@ -2727,7 +2727,7 @@ TEST_F(SyncerTest, WeMovedSomethingIntoAFolderServerHasDeleted) {
   SyncShareAsDelegate();
   SyncShareAsDelegate();
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry bob(&trans, GET_BY_ID, bob_id);
     ASSERT_TRUE(bob.good());
 
@@ -2771,7 +2771,7 @@ class FolderMoveDeleteRenameTest : public SyncerTest {
     ScopedDirLookup dir(syncdb_.manager(), syncdb_.name());
     CHECK(dir.good());
 
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     Entry alice(&trans, GET_BY_ID,
                 TestIdFactory::FromNumber(fred_id_number));
     CHECK(alice.good());
@@ -2805,7 +2805,7 @@ TEST_F(FolderMoveDeleteRenameTest,
       "fred", 1, 10);
   SyncShareAsDelegate();
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry fred(&trans, GET_BY_ID, fred_id);
     ASSERT_TRUE(fred.good());
     fred.Put(IS_UNSYNCED, true);
@@ -2826,7 +2826,7 @@ TEST_F(FolderMoveDeleteRenameTest,
   SyncShareAsDelegate();
   SyncShareAsDelegate();
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry bob(&trans, GET_BY_ID, bob_id);
     ASSERT_TRUE(bob.good());
 
@@ -2865,7 +2865,7 @@ TEST_F(SyncerTest,
   SyncShareAsDelegate();
   syncable::Id new_item_id;
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry bob(&trans, GET_BY_ID, bob_id);
     ASSERT_TRUE(bob.good());
     bob.Put(IS_UNSYNCED, true);
@@ -2881,7 +2881,7 @@ TEST_F(SyncerTest,
   SyncShareAsDelegate();
   SyncShareAsDelegate();
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
 
     Entry bob(&trans, GET_BY_ID, bob_id);
     ASSERT_TRUE(bob.good());
@@ -2915,7 +2915,7 @@ TEST_F(SyncerTest, ServerMovedSomethingIntoAFolderWeHaveDeleted) {
   mock_server_->AddUpdateDirectory(2, 0, "fred", 1, 10);
   LoopSyncShare();
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry bob(&trans, GET_BY_ID, ids_.FromNumber(1));
     ASSERT_TRUE(bob.good());
     bob.Put(IS_UNSYNCED, true);
@@ -2926,7 +2926,7 @@ TEST_F(SyncerTest, ServerMovedSomethingIntoAFolderWeHaveDeleted) {
   LoopSyncShare();
   LoopSyncShare();
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry bob(&trans, GET_BY_ID, ids_.FromNumber(1));
     ASSERT_TRUE(bob.good());
     Entry fred(&trans, GET_BY_ID, ids_.FromNumber(2));
@@ -2949,7 +2949,7 @@ TEST_F(SyncerTest, ServerMovedAFolderIntoAFolderWeHaveDeletedAndMovedIntoIt) {
   mock_server_->AddUpdateDirectory(2, 0, "fred", 1, 10);
   SyncShareAsDelegate();
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry bob(&trans, GET_BY_ID, ids_.FromNumber(1));
     ASSERT_TRUE(bob.good());
     bob.Put(IS_UNSYNCED, true);
@@ -2961,7 +2961,7 @@ TEST_F(SyncerTest, ServerMovedAFolderIntoAFolderWeHaveDeletedAndMovedIntoIt) {
   SyncShareAsDelegate();
   SyncShareAsDelegate();
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry bob(&trans, GET_BY_ID, ids_.FromNumber(1));
     ASSERT_TRUE(bob.good());
     Entry fred(&trans, GET_BY_ID, ids_.FromNumber(2));
@@ -2983,7 +2983,7 @@ TEST_F(SyncerTest, NewServerItemInAFolderWeHaveDeleted) {
   mock_server_->AddUpdateDirectory(1, 0, "bob", 1, 10);
   LoopSyncShare();
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry bob(&trans, GET_BY_ID, ids_.FromNumber(1));
     ASSERT_TRUE(bob.good());
     bob.Put(IS_UNSYNCED, true);
@@ -2994,7 +2994,7 @@ TEST_F(SyncerTest, NewServerItemInAFolderWeHaveDeleted) {
   LoopSyncShare();
   LoopSyncShare();
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry bob(&trans, GET_BY_ID, ids_.FromNumber(1));
     ASSERT_TRUE(bob.good());
     Entry fred(&trans, GET_BY_ID, ids_.FromNumber(2));
@@ -3016,7 +3016,7 @@ TEST_F(SyncerTest, NewServerItemInAFolderHierarchyWeHaveDeleted) {
   mock_server_->AddUpdateDirectory(2, 1, "joe", 1, 10);
   LoopSyncShare();
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry bob(&trans, GET_BY_ID, ids_.FromNumber(1));
     ASSERT_TRUE(bob.good());
     bob.Put(IS_UNSYNCED, true);
@@ -3031,7 +3031,7 @@ TEST_F(SyncerTest, NewServerItemInAFolderHierarchyWeHaveDeleted) {
   LoopSyncShare();
   LoopSyncShare();
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry bob(&trans, GET_BY_ID, ids_.FromNumber(1));
     ASSERT_TRUE(bob.good());
     Entry joe(&trans, GET_BY_ID, ids_.FromNumber(2));
@@ -3061,7 +3061,7 @@ TEST_F(SyncerTest, NewServerItemInAFolderHierarchyWeHaveDeleted2) {
   mock_server_->AddUpdateDirectory(2, 1, "joe", 1, 10);
   LoopSyncShare();
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry bob(&trans, GET_BY_ID, ids_.FromNumber(1));
     ASSERT_TRUE(bob.good());
     bob.Put(IS_UNSYNCED, true);
@@ -3076,7 +3076,7 @@ TEST_F(SyncerTest, NewServerItemInAFolderHierarchyWeHaveDeleted2) {
   LoopSyncShare();
   LoopSyncShare();
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry bob(&trans, GET_BY_ID, ids_.FromNumber(1));
     ASSERT_TRUE(bob.good());
     Entry joe(&trans, GET_BY_ID, ids_.FromNumber(2));
@@ -3116,7 +3116,7 @@ class SusanDeletingTest : public SyncerTest {
     ASSERT_GT(countdown_till_delete_, 0);
     if (0 != --countdown_till_delete_)
     return;
-  WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+  WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry susan(&trans, GET_BY_ID, susan_id);
   Directory::ChildHandles children;
   dir->GetChildHandlesById(&trans, susan.Get(ID), &children);
@@ -3147,7 +3147,7 @@ TEST_F(SusanDeletingTest,
   mock_server_->AddUpdateDirectory(joe_id, bob_id, "joe", 1, 10);
   LoopSyncShare();
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry bob(&trans, GET_BY_ID, bob_id);
     ASSERT_TRUE(bob.good());
     bob.Put(IS_UNSYNCED, true);
@@ -3167,7 +3167,7 @@ TEST_F(SusanDeletingTest,
   SyncShareAsDelegate();
   SyncShareAsDelegate();
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry bob(&trans, GET_BY_ID, bob_id);
     ASSERT_TRUE(bob.good());
     Entry joe(&trans, GET_BY_ID, joe_id);
@@ -3191,7 +3191,7 @@ TEST_F(SusanDeletingTest,
   LoopSyncShare();
   LoopSyncShare();
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry bob(&trans, GET_BY_ID, bob_id);
     ASSERT_TRUE(bob.good());
     Entry joe(&trans, GET_BY_ID, joe_id);
@@ -3231,7 +3231,7 @@ TEST_F(SyncerTest, WeMovedSomethingIntoAFolderHierarchyServerHasDeleted) {
   mock_server_->AddUpdateDirectory(alice_id, fred_id, "alice", 1, 10);
   SyncShareAsDelegate();
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry bob(&trans, GET_BY_ID, bob_id);
     ASSERT_TRUE(bob.good());
     bob.Put(IS_UNSYNCED, true);
@@ -3249,7 +3249,7 @@ TEST_F(SyncerTest, WeMovedSomethingIntoAFolderHierarchyServerHasDeleted) {
   {
     // Bob is the entry at the bottom of the tree.
     // The tree should be regenerated and old IDs removed.
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry bob(&trans, GET_BY_ID, bob_id);
     ASSERT_TRUE(bob.good());
     EXPECT_FALSE(bob.Get(IS_UNAPPLIED_UPDATE));
@@ -3303,7 +3303,7 @@ TEST_F(SyncerTest, WeMovedSomethingIntoAFolderHierarchyServerHasDeleted2) {
   mock_server_->AddUpdateDirectory(alice_id, fred_id, "alice", 1, 10);
   SyncShareAsDelegate();
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry bob(&trans, GET_BY_ID, bob_id);
     ASSERT_TRUE(bob.good());
     bob.Put(IS_UNSYNCED, true);
@@ -3325,7 +3325,7 @@ TEST_F(SyncerTest, WeMovedSomethingIntoAFolderHierarchyServerHasDeleted2) {
     //            |- Alice
     //                 |- Bob
 
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry bob(&trans, GET_BY_ID, bob_id);
     ASSERT_TRUE(bob.good());
     EXPECT_FALSE(bob.Get(IS_UNAPPLIED_UPDATE));
@@ -3370,7 +3370,7 @@ TEST_F(SyncerTest, DuplicateIDReturn) {
   ScopedDirLookup dir(syncdb_.manager(), syncdb_.name());
   ASSERT_TRUE(dir.good());
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry folder(&trans, CREATE, trans.root_id(), "bob");
     ASSERT_TRUE(folder.good());
     folder.Put(IS_UNSYNCED, true);
@@ -3400,7 +3400,7 @@ TEST_F(SyncerTest, DeletedEntryWithBadParentInLoopCalculation) {
   mock_server_->AddUpdateDirectory(1, 0, "bob", 1, 10);
   SyncShareAsDelegate();
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry bob(&trans, GET_BY_ID, ids_.FromNumber(1));
     ASSERT_TRUE(bob.good());
     // This is valid, because the parent could have gone away a long time ago.
@@ -3421,7 +3421,7 @@ TEST_F(SyncerTest, ConflictResolverMergeOverwritesLocalEntry) {
 
   ConflictSet conflict_set;
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
 
     MutableEntry local_deleted(&trans, CREATE, trans.root_id(), "name");
     local_deleted.Put(ID, ids_.FromNumber(1));
@@ -3443,7 +3443,7 @@ TEST_F(SyncerTest, ConflictResolverMergeOverwritesLocalEntry) {
     conflict_set.push_back(ids_.FromNumber(3));
   }
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     context_->resolver()->ProcessConflictSet(&trans, &conflict_set, 50);
   }
 }
@@ -3453,7 +3453,7 @@ TEST_F(SyncerTest, ConflictResolverMergesLocalDeleteAndServerUpdate) {
   CHECK(dir.good());
 
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
 
     MutableEntry local_deleted(&trans, CREATE, trans.root_id(), "name");
     local_deleted.Put(ID, ids_.FromNumber(1));
@@ -3471,7 +3471,7 @@ TEST_F(SyncerTest, ConflictResolverMergesLocalDeleteAndServerUpdate) {
   SyncShareAsDelegate();
 
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry local_deleted(&trans, GET_BY_ID, ids_.FromNumber(1));
     EXPECT_TRUE(local_deleted.Get(BASE_VERSION) == 10);
     EXPECT_TRUE(local_deleted.Get(IS_UNAPPLIED_UPDATE) == false);
@@ -3489,7 +3489,7 @@ TEST_F(SyncerTest, UpdateFlipsTheFolderBit) {
 
   // Local object: a deleted directory (container), revision 1, unsynced.
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
 
     MutableEntry local_deleted(&trans, CREATE, trans.root_id(), "name");
     local_deleted.Put(ID, ids_.FromNumber(1));
@@ -3510,7 +3510,7 @@ TEST_F(SyncerTest, UpdateFlipsTheFolderBit) {
   SyncShareAsDelegate();
 
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry local_deleted(&trans, GET_BY_ID, ids_.FromNumber(1));
     EXPECT_TRUE(local_deleted.Get(BASE_VERSION) == 1);
     EXPECT_TRUE(local_deleted.Get(IS_UNAPPLIED_UPDATE) == false);
@@ -3563,7 +3563,7 @@ TEST_F(SyncerTest, MergingExistingItems) {
   mock_server_->AddUpdateBookmark(1, 0, "base", 10, 10);
   SyncShareAsDelegate();
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry entry(&trans, CREATE, trans.root_id(), "Copy of base");
     WriteTestDataToEntry(&trans, &entry);
   }
@@ -3619,7 +3619,7 @@ TEST_F(SyncerTest, LongChangelistWithApplicationConflict) {
 
   // Ensure our folder hasn't somehow applied.
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry child(&trans, GET_BY_ID, stuck_entry_id);
     EXPECT_TRUE(child.good());
     EXPECT_TRUE(child.Get(IS_UNAPPLIED_UPDATE));
@@ -3635,7 +3635,7 @@ TEST_F(SyncerTest, LongChangelistWithApplicationConflict) {
   LoopSyncShare();
   // Check that everything is as expected after the commit.
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry entry(&trans, GET_BY_ID, folder_id);
     ASSERT_TRUE(entry.good());
     Entry child(&trans, GET_BY_ID, stuck_entry_id);
@@ -3653,7 +3653,7 @@ TEST_F(SyncerTest, DontMergeTwoExistingItems) {
   mock_server_->AddUpdateBookmark(2, 0, "base2", 10, 10);
   SyncShareAsDelegate();
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry entry(&trans, GET_BY_ID, ids_.FromNumber(2));
     ASSERT_TRUE(entry.good());
     EXPECT_TRUE(entry.Put(NON_UNIQUE_NAME, "Copy of base"));
@@ -3662,7 +3662,7 @@ TEST_F(SyncerTest, DontMergeTwoExistingItems) {
   mock_server_->AddUpdateBookmark(1, 0, "Copy of base", 50, 50);
   SyncRepeatedlyToTriggerConflictResolution(session_.get());
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry entry1(&trans, GET_BY_ID, ids_.FromNumber(1));
     EXPECT_FALSE(entry1.Get(IS_UNAPPLIED_UPDATE));
     EXPECT_FALSE(entry1.Get(IS_UNSYNCED));
@@ -3688,7 +3688,7 @@ TEST_F(SyncerTest, TestUndeleteUpdate) {
 
   int64 metahandle;
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry entry(&trans, GET_BY_ID, ids_.FromNumber(2));
     ASSERT_TRUE(entry.good());
     EXPECT_TRUE(entry.Get(IS_DEL));
@@ -3702,7 +3702,7 @@ TEST_F(SyncerTest, TestUndeleteUpdate) {
   mock_server_->AddUpdateDirectory(2, 1, "bar", 3, 5);
   SyncShareAsDelegate();
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry entry(&trans, GET_BY_ID, ids_.FromNumber(2));
     ASSERT_TRUE(entry.good());
     EXPECT_TRUE(entry.Get(IS_DEL));
@@ -3719,7 +3719,7 @@ TEST_F(SyncerTest, TestMoveSanitizedNamedFolder) {
   mock_server_->AddUpdateDirectory(2, 0, ":::", 1, 2);
   SyncShareAsDelegate();
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry entry(&trans, GET_BY_ID, ids_.FromNumber(2));
     ASSERT_TRUE(entry.good());
     EXPECT_TRUE(entry.Put(PARENT_ID, ids_.FromNumber(1)));
@@ -3740,7 +3740,7 @@ TEST_F(SyncerTest, UpdateWhereParentIsNotAFolder) {
   // Used to cause a CHECK
   SyncShareAsDelegate();
   {
-    ReadTransaction rtrans(dir, FROM_HERE);
+    ReadTransaction rtrans(FROM_HERE, dir);
     Entry good_entry(&rtrans, syncable::GET_BY_ID, ids_.FromNumber(1));
     ASSERT_TRUE(good_entry.good());
     EXPECT_FALSE(good_entry.Get(IS_UNAPPLIED_UPDATE));
@@ -3765,7 +3765,7 @@ TEST_F(SyncerTest, DirectoryUpdateTest) {
                                    "in_in_root_name", 3, 3);
   SyncShareAsDelegate();
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry in_root(&trans, GET_BY_ID, in_root_id);
     ASSERT_TRUE(in_root.good());
     EXPECT_EQ("in_root_name", in_root.Get(NON_UNIQUE_NAME));
@@ -3787,7 +3787,7 @@ TEST_F(SyncerTest, DirectoryCommitTest) {
   int64 bar_metahandle;
 
   {
-    WriteTransaction wtrans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction wtrans(FROM_HERE, UNITTEST, dir);
     MutableEntry parent(&wtrans, syncable::CREATE, root_id_, "foo");
     ASSERT_TRUE(parent.good());
     parent.Put(syncable::IS_UNSYNCED, true);
@@ -3806,7 +3806,7 @@ TEST_F(SyncerTest, DirectoryCommitTest) {
   }
   SyncShareAsDelegate();
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry fail_by_old_id_entry(&trans, GET_BY_ID, in_root_id);
     ASSERT_FALSE(fail_by_old_id_entry.good());
 
@@ -3833,7 +3833,7 @@ TEST_F(SyncerTest, ConflictSetSizeReducedToOne) {
       "in_root", 1, 1);
   SyncShareAsDelegate();
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry oentry(&trans, GET_BY_ID, in_root_id);
     ASSERT_TRUE(oentry.good());
     oentry.Put(NON_UNIQUE_NAME, "old_in_root");
@@ -3890,7 +3890,7 @@ TEST_F(SyncerTest, EnsureWeSendUpOldParent) {
   SyncShareAsDelegate();
   {
     // A moved entry should send an "old parent."
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry entry(&trans, GET_BY_ID, folder_one_id);
     ASSERT_TRUE(entry.good());
     entry.Put(PARENT_ID, folder_two_id);
@@ -3917,7 +3917,7 @@ TEST_F(SyncerTest, Test64BitVersionSupport) {
 
   // Try writing max int64 to the version fields of a meta entry.
   {
-    WriteTransaction wtrans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction wtrans(FROM_HERE, UNITTEST, dir);
     MutableEntry entry(&wtrans, syncable::CREATE, wtrans.root_id(), name);
     ASSERT_TRUE(entry.good());
     entry.Put(syncable::BASE_VERSION, really_big_int);
@@ -3926,7 +3926,7 @@ TEST_F(SyncerTest, Test64BitVersionSupport) {
     item_metahandle = entry.Get(META_HANDLE);
   }
   // Now read it back out and make sure the value is max int64.
-  ReadTransaction rtrans(dir, FROM_HERE);
+  ReadTransaction rtrans(FROM_HERE, dir);
   Entry entry(&rtrans, syncable::GET_BY_HANDLE, item_metahandle);
   ASSERT_TRUE(entry.good());
   EXPECT_TRUE(really_big_int == entry.Get(syncable::BASE_VERSION));
@@ -3942,7 +3942,7 @@ TEST_F(SyncerTest, TestSimpleUndelete) {
   SyncShareAsDelegate();
   // Check it out and delete it.
   {
-    WriteTransaction wtrans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction wtrans(FROM_HERE, UNITTEST, dir);
     MutableEntry entry(&wtrans, GET_BY_ID, id);
     ASSERT_TRUE(entry.good());
     EXPECT_FALSE(entry.Get(IS_UNAPPLIED_UPDATE));
@@ -3954,7 +3954,7 @@ TEST_F(SyncerTest, TestSimpleUndelete) {
   SyncShareAsDelegate();
   // Confirm we see IS_DEL and not SERVER_IS_DEL.
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry entry(&trans, GET_BY_ID, id);
     ASSERT_TRUE(entry.good());
     EXPECT_FALSE(entry.Get(IS_UNAPPLIED_UPDATE));
@@ -3969,7 +3969,7 @@ TEST_F(SyncerTest, TestSimpleUndelete) {
   SyncShareAsDelegate();
   // IS_DEL AND SERVER_IS_DEL now both true.
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry entry(&trans, GET_BY_ID, id);
     ASSERT_TRUE(entry.good());
     EXPECT_FALSE(entry.Get(IS_UNAPPLIED_UPDATE));
@@ -3982,7 +3982,7 @@ TEST_F(SyncerTest, TestSimpleUndelete) {
   SyncShareAsDelegate();
   // IS_DEL and SERVER_IS_DEL now both false.
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry entry(&trans, GET_BY_ID, id);
     ASSERT_TRUE(entry.good());
     EXPECT_FALSE(entry.Get(IS_UNAPPLIED_UPDATE));
@@ -4002,7 +4002,7 @@ TEST_F(SyncerTest, TestUndeleteWithMissingDeleteUpdate) {
   SyncShareAsDelegate();
   // Check it out and delete it.
   {
-    WriteTransaction wtrans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction wtrans(FROM_HERE, UNITTEST, dir);
     MutableEntry entry(&wtrans, GET_BY_ID, id);
     ASSERT_TRUE(entry.good());
     EXPECT_FALSE(entry.Get(IS_UNAPPLIED_UPDATE));
@@ -4014,7 +4014,7 @@ TEST_F(SyncerTest, TestUndeleteWithMissingDeleteUpdate) {
   SyncShareAsDelegate();
   // Confirm we see IS_DEL and not SERVER_IS_DEL.
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry entry(&trans, GET_BY_ID, id);
     ASSERT_TRUE(entry.good());
     EXPECT_FALSE(entry.Get(IS_UNAPPLIED_UPDATE));
@@ -4029,7 +4029,7 @@ TEST_F(SyncerTest, TestUndeleteWithMissingDeleteUpdate) {
   SyncShareAsDelegate();
   // IS_DEL and SERVER_IS_DEL now both false.
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry entry(&trans, GET_BY_ID, id);
     ASSERT_TRUE(entry.good());
     EXPECT_FALSE(entry.Get(IS_UNAPPLIED_UPDATE));
@@ -4063,7 +4063,7 @@ TEST_F(SyncerTest, ClientTagServerCreatedUpdatesWork) {
   SyncShareAsDelegate();
 
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry perm_folder(&trans, GET_BY_CLIENT_TAG, "permfolder");
     ASSERT_TRUE(perm_folder.good());
     EXPECT_FALSE(perm_folder.Get(IS_DEL));
@@ -4078,7 +4078,7 @@ TEST_F(SyncerTest, ClientTagServerCreatedUpdatesWork) {
   SyncShareAsDelegate();
 
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
 
     Entry perm_folder(&trans, GET_BY_CLIENT_TAG, "permfolder");
     ASSERT_TRUE(perm_folder.good());
@@ -4100,7 +4100,7 @@ TEST_F(SyncerTest, ClientTagIllegalUpdateIgnored) {
   SyncShareAsDelegate();
 
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry perm_folder(&trans, GET_BY_CLIENT_TAG, "permfolder");
     ASSERT_TRUE(perm_folder.good());
     EXPECT_FALSE(perm_folder.Get(IS_UNAPPLIED_UPDATE));
@@ -4115,7 +4115,7 @@ TEST_F(SyncerTest, ClientTagIllegalUpdateIgnored) {
   SyncShareAsDelegate();
 
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
 
     // This update is rejected because it has the same ID, but a
     // different tag than one that is already on the client.
@@ -4144,7 +4144,7 @@ TEST_F(SyncerTest, ClientTagUncommittedTagMatchesUpdate) {
       set_url("http://bar/serversite");
 
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry perm_folder(&trans, CREATE, ids_.root(), "clientname");
     ASSERT_TRUE(perm_folder.good());
     perm_folder.Put(UNIQUE_CLIENT_TAG, "clientperm");
@@ -4164,7 +4164,7 @@ TEST_F(SyncerTest, ClientTagUncommittedTagMatchesUpdate) {
   SyncShareAsDelegate();
   // This should cause client tag reunion, preserving the metahandle.
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
 
     Entry perm_folder(&trans, GET_BY_CLIENT_TAG, "clientperm");
     ASSERT_TRUE(perm_folder.good());
@@ -4187,7 +4187,7 @@ TEST_F(SyncerTest, ClientTagUncommittedTagMatchesUpdate) {
 
   // The resolved entry ought to commit cleanly.
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
 
     Entry perm_folder(&trans, GET_BY_CLIENT_TAG, "clientperm");
     ASSERT_TRUE(perm_folder.good());
@@ -4211,7 +4211,7 @@ TEST_F(SyncerTest, ClientTagConflictWithDeletedLocalEntry) {
   EXPECT_TRUE(dir.good());
 
   {
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry perm_folder(&trans, CREATE, ids_.root(), "clientname");
     ASSERT_TRUE(perm_folder.good());
     ASSERT_FALSE(perm_folder.Get(ID).ServerKnows());
@@ -4228,7 +4228,7 @@ TEST_F(SyncerTest, ClientTagConflictWithDeletedLocalEntry) {
   SyncShareAsDelegate();
   // This should cause client tag overwrite.
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
 
     Entry perm_folder(&trans, GET_BY_CLIENT_TAG, "clientperm");
     ASSERT_TRUE(perm_folder.good());
@@ -4262,7 +4262,7 @@ TEST_F(SyncerTest, ClientTagUpdateClashesWithLocalEntry) {
   int64 tag2_metahandle = syncable::kInvalidMetaHandle;
   // This should cause client tag overwrite.
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
 
     Entry tag1(&trans, GET_BY_CLIENT_TAG, "tag1");
     ASSERT_TRUE(tag1.good());
@@ -4300,7 +4300,7 @@ TEST_F(SyncerTest, ClientTagUpdateClashesWithLocalEntry) {
   SyncShareAsDelegate();
 
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
 
     Entry tag1(&trans, GET_BY_CLIENT_TAG, "tag1");
     ASSERT_TRUE(tag1.good());
@@ -4375,7 +4375,7 @@ TEST_F(SyncerTest, ClientTagClashWithinBatchOfUpdates) {
   SyncShareAsDelegate();
   // This should cause client tag overwrite.
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
 
     Entry tag_a(&trans, GET_BY_CLIENT_TAG, "tag a");
     ASSERT_TRUE(tag_a.good());
@@ -4423,7 +4423,7 @@ TEST_F(SyncerTest, UniqueServerTagUpdates) {
   // we'll use later.
   int64 hurdle_handle = CreateUnsyncedDirectory("bob", "id_bob");
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry hurdle(&trans, GET_BY_HANDLE, hurdle_handle);
     ASSERT_TRUE(hurdle.good());
     ASSERT_TRUE(!hurdle.Get(IS_DEL));
@@ -4445,7 +4445,7 @@ TEST_F(SyncerTest, UniqueServerTagUpdates) {
   SyncShareAsDelegate();
 
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
 
     // The new items should be applied as new entries, and we should be able
     // to look them up by their tag values.
@@ -4527,7 +4527,7 @@ class SyncerUndeletionTest : public SyncerTest {
   void Create() {
     ScopedDirLookup dir(syncdb_.manager(), syncdb_.name());
     EXPECT_TRUE(dir.good());
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry perm_folder(&trans, CREATE, ids_.root(), "clientname");
     ASSERT_TRUE(perm_folder.good());
     perm_folder.Put(UNIQUE_CLIENT_TAG, client_tag_);
@@ -4542,7 +4542,7 @@ class SyncerUndeletionTest : public SyncerTest {
   void Delete() {
     ScopedDirLookup dir(syncdb_.manager(), syncdb_.name());
     EXPECT_TRUE(dir.good());
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry entry(&trans, GET_BY_CLIENT_TAG, client_tag_);
     ASSERT_TRUE(entry.good());
     EXPECT_EQ(metahandle_, entry.Get(META_HANDLE));
@@ -4554,7 +4554,7 @@ class SyncerUndeletionTest : public SyncerTest {
   void Undelete() {
     ScopedDirLookup dir(syncdb_.manager(), syncdb_.name());
     EXPECT_TRUE(dir.good());
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry entry(&trans, GET_BY_CLIENT_TAG, client_tag_);
     ASSERT_TRUE(entry.good());
     EXPECT_EQ(metahandle_, entry.Get(META_HANDLE));
@@ -4567,7 +4567,7 @@ class SyncerUndeletionTest : public SyncerTest {
   int64 GetMetahandleOfTag() {
     ScopedDirLookup dir(syncdb_.manager(), syncdb_.name());
     EXPECT_TRUE(dir.good());
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Entry entry(&trans, GET_BY_CLIENT_TAG, client_tag_);
     EXPECT_TRUE(entry.good());
     if (!entry.good()) {
@@ -4976,7 +4976,7 @@ class SyncerPositionUpdateTest : public SyncerTest {
 
     ScopedDirLookup dir(syncdb_.manager(), syncdb_.name());
     EXPECT_TRUE(dir.good());
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
 
     Id prev_id;
     DCHECK(prev_id.IsRoot());
@@ -5104,7 +5104,7 @@ class SyncerPositionTiebreakingTest : public SyncerTest {
   void ExpectLocalOrderIsByServerId() {
     ScopedDirLookup dir(syncdb_.manager(), syncdb_.name());
     EXPECT_TRUE(dir.good());
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     Id null_id;
     Entry low(&trans, GET_BY_ID, low_id_);
     Entry mid(&trans, GET_BY_ID, mid_id_);
diff --git a/chrome/browser/sync/engine/syncer_util.cc b/chrome/browser/sync/engine/syncer_util.cc
index d61059c..090b07f 100644
--- a/chrome/browser/sync/engine/syncer_util.cc
+++ b/chrome/browser/sync/engine/syncer_util.cc
@@ -660,7 +660,7 @@ void SyncerUtil::MarkDeletedChildrenSynced(
     return;
   Directory::UnsyncedMetaHandles handles;
   {
-    ReadTransaction trans(dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir);
     dir->GetUnsyncedMetaHandles(&trans, &handles);
   }
   if (handles.empty())
@@ -668,7 +668,7 @@ void SyncerUtil::MarkDeletedChildrenSynced(
   Directory::UnsyncedMetaHandles::iterator it;
   for (it = handles.begin() ; it != handles.end() ; ++it) {
     // Single transaction / entry we deal with.
-    WriteTransaction trans(dir, SYNCER, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, SYNCER, dir);
     MutableEntry entry(&trans, GET_BY_HANDLE, *it);
     if (!entry.Get(IS_UNSYNCED) || !entry.Get(IS_DEL))
       continue;
diff --git a/chrome/browser/sync/engine/verify_updates_command.cc b/chrome/browser/sync/engine/verify_updates_command.cc
index cec103b..fe83446 100644
--- a/chrome/browser/sync/engine/verify_updates_command.cc
+++ b/chrome/browser/sync/engine/verify_updates_command.cc
@@ -35,7 +35,7 @@ void VerifyUpdatesCommand::ModelChangingExecuteImpl(
     LOG(ERROR) << "Scoped dir lookup failed!";
     return;
   }
-  WriteTransaction trans(dir, SYNCER, FROM_HERE);
+  WriteTransaction trans(FROM_HERE, SYNCER, dir);
   sessions::StatusController* status = session->status_controller();
   const GetUpdatesResponse& updates = status->updates_response().get_updates();
   int update_count = updates.entries().size();
diff --git a/chrome/browser/sync/engine/verify_updates_command_unittest.cc b/chrome/browser/sync/engine/verify_updates_command_unittest.cc
index 6273d55..9713d63 100644
--- a/chrome/browser/sync/engine/verify_updates_command_unittest.cc
+++ b/chrome/browser/sync/engine/verify_updates_command_unittest.cc
@@ -44,7 +44,7 @@ class VerifyUpdatesCommandTest : public SyncerCommandTest {
                        const syncable::ModelType& type) {
     ScopedDirLookup dir(syncdb()->manager(), syncdb()->name());
     ASSERT_TRUE(dir.good());
-    WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir);
     MutableEntry entry(&trans, syncable::CREATE_NEW_UPDATE_ITEM,
         Id::CreateFromServerId(item_id));
     ASSERT_TRUE(entry.good());
diff --git a/chrome/browser/sync/glue/app_model_associator.cc b/chrome/browser/sync/glue/app_model_associator.cc
index b2bb54c..fd6dd24 100644
--- a/chrome/browser/sync/glue/app_model_associator.cc
+++ b/chrome/browser/sync/glue/app_model_associator.cc
@@ -5,6 +5,7 @@
 #include "chrome/browser/sync/glue/app_model_associator.h"
 
 #include "base/logging.h"
+#include "base/tracked.h"
 #include "chrome/browser/extensions/extension_sync_data.h"
 #include "chrome/browser/sync/engine/syncapi.h"
 #include "chrome/browser/sync/glue/extension_sync_traits.h"
@@ -63,7 +64,7 @@ void AppModelAssociator::AbortAssociation() {
 
 bool AppModelAssociator::CryptoReadyIfNecessary() {
   // We only access the cryptographer while holding a transaction.
-  sync_api::ReadTransaction trans(user_share_);
+  sync_api::ReadTransaction trans(FROM_HERE, user_share_);
   const syncable::ModelTypeSet& encrypted_types =
       sync_api::GetEncryptedTypes(&trans);
   return encrypted_types.count(traits_.model_type) == 0 ||
diff --git a/chrome/browser/sync/glue/autofill_change_processor.cc b/chrome/browser/sync/glue/autofill_change_processor.cc
index 00be75c..b37830d 100644
--- a/chrome/browser/sync/glue/autofill_change_processor.cc
+++ b/chrome/browser/sync/glue/autofill_change_processor.cc
@@ -8,6 +8,7 @@
 #include <vector>
 
 #include "base/string_util.h"
+#include "base/tracked.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/browser/autofill/personal_data_manager.h"
 #include "chrome/browser/profiles/profile.h"
@@ -67,7 +68,7 @@ void AutofillChangeProcessor::Observe(NotificationType type,
   if (!observing_)
     return;
 
-  sync_api::WriteTransaction trans(share_handle());
+  sync_api::WriteTransaction trans(FROM_HERE, share_handle());
   sync_api::ReadNode autofill_root(&trans);
   if (!autofill_root.InitByTagLookup(kAutofillTag)) {
     error_handler()->OnUnrecoverableError(FROM_HERE,
diff --git a/chrome/browser/sync/glue/autofill_model_associator.cc b/chrome/browser/sync/glue/autofill_model_associator.cc
index d783f19..72951b6 100644
--- a/chrome/browser/sync/glue/autofill_model_associator.cc
+++ b/chrome/browser/sync/glue/autofill_model_associator.cc
@@ -10,6 +10,7 @@
 #include "base/string_number_conversions.h"
 #include "base/task.h"
 #include "base/time.h"
+#include "base/tracked.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/browser/autofill/autofill_profile.h"
 #include "chrome/browser/profiles/profile.h"
@@ -156,7 +157,7 @@ bool AutofillModelAssociator::AssociateModels() {
 
   DataBundle bundle;
   {
-    sync_api::WriteTransaction trans(sync_service_->GetUserShare());
+    sync_api::WriteTransaction trans(FROM_HERE, sync_service_->GetUserShare());
 
     sync_api::ReadNode autofill_root(&trans);
     if (!autofill_root.InitByTagLookup(kAutofillTag)) {
@@ -394,7 +395,7 @@ bool AutofillModelAssociator::SyncModelHasUserCreatedNodes(bool* has_nodes) {
                << "might be running against an out-of-date server.";
     return false;
   }
-  sync_api::ReadTransaction trans(sync_service_->GetUserShare());
+  sync_api::ReadTransaction trans(FROM_HERE, sync_service_->GetUserShare());
 
   sync_api::ReadNode autofill_node(&trans);
   if (!autofill_node.InitByIdLookup(autofill_sync_id)) {
@@ -454,7 +455,7 @@ void AutofillModelAssociator::Disassociate(int64 sync_id) {
 
 bool AutofillModelAssociator::GetSyncIdForTaggedNode(const std::string& tag,
                                                      int64* sync_id) {
-  sync_api::ReadTransaction trans(sync_service_->GetUserShare());
+  sync_api::ReadTransaction trans(FROM_HERE, sync_service_->GetUserShare());
   sync_api::ReadNode sync_node(&trans);
   if (!sync_node.InitByTagLookup(tag.c_str()))
     return false;
@@ -585,7 +586,7 @@ bool AutofillModelAssociator::HasNotMigratedYet(
 
 bool AutofillModelAssociator::CryptoReadyIfNecessary() {
   // We only access the cryptographer while holding a transaction.
-  sync_api::ReadTransaction trans(sync_service_->GetUserShare());
+  sync_api::ReadTransaction trans(FROM_HERE, sync_service_->GetUserShare());
   syncable::ModelTypeSet encrypted_types;
   encrypted_types = sync_api::GetEncryptedTypes(&trans);
   return encrypted_types.count(syncable::AUTOFILL) == 0 ||
diff --git a/chrome/browser/sync/glue/autofill_profile_change_processor.cc b/chrome/browser/sync/glue/autofill_profile_change_processor.cc
index 36b1372..ac6099c 100644
--- a/chrome/browser/sync/glue/autofill_profile_change_processor.cc
+++ b/chrome/browser/sync/glue/autofill_profile_change_processor.cc
@@ -8,6 +8,7 @@
 #include <vector>
 
 #include "base/string_util.h"
+#include "base/tracked.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/browser/autofill/autofill_profile.h"
 #include "chrome/browser/autofill/personal_data_manager.h"
@@ -100,7 +101,7 @@ void AutofillProfileChangeProcessor::Observe(NotificationType type,
   if (!wds || wds->GetDatabase() != web_database_)
     return;
 
-  sync_api::WriteTransaction trans(share_handle());
+  sync_api::WriteTransaction trans(FROM_HERE, share_handle());
   sync_api::ReadNode autofill_root(&trans);
   if (!autofill_root.InitByTagLookup(kAutofillProfileTag)) {
     error_handler()->OnUnrecoverableError(FROM_HERE,
diff --git a/chrome/browser/sync/glue/autofill_profile_model_associator.cc b/chrome/browser/sync/glue/autofill_profile_model_associator.cc
index 4b45880..3fe51aa 100644
--- a/chrome/browser/sync/glue/autofill_profile_model_associator.cc
+++ b/chrome/browser/sync/glue/autofill_profile_model_associator.cc
@@ -4,6 +4,7 @@
 
 #include "chrome/browser/sync/glue/autofill_profile_model_associator.h"
 
+#include "base/tracked.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/browser/sync/glue/autofill_profile_change_processor.h"
 #include "chrome/browser/sync/glue/do_optimistic_refresh_task.h"
@@ -116,7 +117,7 @@ bool AutofillProfileModelAssociator::TraverseAndAssociateChromeAutofillProfiles(
 bool AutofillProfileModelAssociator::GetSyncIdForTaggedNode(
     const std::string& tag,
     int64* sync_id) {
-  sync_api::ReadTransaction trans(sync_service_->GetUserShare());
+  sync_api::ReadTransaction trans(FROM_HERE, sync_service_->GetUserShare());
   sync_api::ReadNode sync_node(&trans);
   if (!sync_node.InitByTagLookup(tag.c_str()))
     return false;
@@ -157,7 +158,7 @@ bool AutofillProfileModelAssociator::AssociateModels() {
   {
     // The write transaction lock is held inside this block.
     // We do all the web db operations outside this block.
-    sync_api::WriteTransaction trans(sync_service_->GetUserShare());
+    sync_api::WriteTransaction trans(FROM_HERE, sync_service_->GetUserShare());
 
     sync_api::ReadNode autofill_root(&trans);
     if (!autofill_root.InitByTagLookup(kAutofillProfileTag)) {
@@ -218,7 +219,7 @@ bool AutofillProfileModelAssociator::MergeField(FormGroup* f,
 bool AutofillProfileModelAssociator::SyncModelHasUserCreatedNodes(
     bool *has_nodes) {
   CHECK_NE(has_nodes, reinterpret_cast<bool*>(NULL));
-  sync_api::ReadTransaction trans(sync_service_->GetUserShare());
+  sync_api::ReadTransaction trans(FROM_HERE, sync_service_->GetUserShare());
 
   sync_api::ReadNode node(&trans);
 
@@ -506,7 +507,7 @@ AutofillProfileModelAssociator::DataBundle::~DataBundle() {
 
 bool AutofillProfileModelAssociator::CryptoReadyIfNecessary() {
   // We only access the cryptographer while holding a transaction.
-  sync_api::ReadTransaction trans(sync_service_->GetUserShare());
+  sync_api::ReadTransaction trans(FROM_HERE, sync_service_->GetUserShare());
   syncable::ModelTypeSet encrypted_types;
   encrypted_types = sync_api::GetEncryptedTypes(&trans);
   return encrypted_types.count(syncable::AUTOFILL_PROFILE) == 0 ||
diff --git a/chrome/browser/sync/glue/autofill_profile_model_associator_unittest.cc b/chrome/browser/sync/glue/autofill_profile_model_associator_unittest.cc
index e1792a6..909b895 100644
--- a/chrome/browser/sync/glue/autofill_profile_model_associator_unittest.cc
+++ b/chrome/browser/sync/glue/autofill_profile_model_associator_unittest.cc
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#include "base/tracked.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/browser/sync/engine/read_node_mock.h"
 #include "chrome/browser/sync/engine/syncapi_mock.h"
@@ -115,7 +116,7 @@ TEST_F(AutofillProfileModelAssociatorTest,
   kernel.put(syncable::SPECIFICS, specifics);
   kernel.put(syncable::META_HANDLE, 1);
 
-  MockWriteTransaction write_trans(&mock_directory);
+  MockWriteTransaction write_trans(FROM_HERE, &mock_directory);
   EXPECT_CALL(mock_directory, GetEntryByClientTag(_))
              .WillOnce(Return(&kernel));
 
@@ -140,7 +141,7 @@ TEST_F(AutofillProfileModelAssociatorTest, TestAssociatingMissingWebDBProfile) {
   ScopedVector<AutofillProfile> profiles_from_web_db;
   MockDirectory mock_directory;
 
-  MockWriteTransaction write_trans(&mock_directory);
+  MockWriteTransaction write_trans(FROM_HERE, &mock_directory);
   EXPECT_CALL(mock_directory,
               GetEntryByClientTag(_))
              .WillOnce(Return(reinterpret_cast<EntryKernel*>(NULL)));
@@ -191,7 +192,7 @@ TEST_F(AutofillProfileModelAssociatorTest,
   kernel.put(syncable::META_HANDLE, 1);
   kernel.put(syncable::ID, root_id);
 
-  MockWriteTransaction write_trans(&mock_directory);
+  MockWriteTransaction write_trans(FROM_HERE, &mock_directory);
 
   browser_sync::AutofillProfileModelAssociator::DataBundle bundle;
 
diff --git a/chrome/browser/sync/glue/bookmark_change_processor.cc b/chrome/browser/sync/glue/bookmark_change_processor.cc
index da0605c..495753d 100644
--- a/chrome/browser/sync/glue/bookmark_change_processor.cc
+++ b/chrome/browser/sync/glue/bookmark_change_processor.cc
@@ -8,7 +8,7 @@
 
 #include "base/string16.h"
 #include "base/string_util.h"
-
+#include "base/tracked.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/browser/bookmarks/bookmark_utils.h"
 #include "chrome/browser/favicon/favicon_service.h"
@@ -92,7 +92,7 @@ void BookmarkChangeProcessor::RemoveOneSyncNode(
 
 void BookmarkChangeProcessor::RemoveSyncNodeHierarchy(
     const BookmarkNode* topmost) {
-  sync_api::WriteTransaction trans(share_handle());
+  sync_api::WriteTransaction trans(FROM_HERE, share_handle());
 
   // Later logic assumes that |topmost| has been unlinked.
   DCHECK(topmost->is_root());
@@ -145,7 +145,7 @@ void BookmarkChangeProcessor::BookmarkNodeAdded(BookmarkModel* model,
   DCHECK(share_handle());
 
   // Acquire a scoped write lock via a transaction.
-  sync_api::WriteTransaction trans(share_handle());
+  sync_api::WriteTransaction trans(FROM_HERE, share_handle());
 
   CreateSyncNode(parent, model, index, &trans, model_associator_,
                  error_handler());
@@ -197,7 +197,7 @@ void BookmarkChangeProcessor::BookmarkNodeChanged(BookmarkModel* model,
   }
 
   // Acquire a scoped write lock via a transaction.
-  sync_api::WriteTransaction trans(share_handle());
+  sync_api::WriteTransaction trans(FROM_HERE, share_handle());
 
   // Lookup the sync node that's associated with |node|.
   sync_api::WriteNode sync_node(&trans);
@@ -231,7 +231,7 @@ void BookmarkChangeProcessor::BookmarkNodeMoved(BookmarkModel* model,
   }
 
   // Acquire a scoped write lock via a transaction.
-  sync_api::WriteTransaction trans(share_handle());
+  sync_api::WriteTransaction trans(FROM_HERE, share_handle());
 
   // Lookup the sync node that's associated with |child|.
   sync_api::WriteNode sync_node(&trans);
@@ -258,7 +258,7 @@ void BookmarkChangeProcessor::BookmarkNodeChildrenReordered(
     BookmarkModel* model, const BookmarkNode* node) {
 
   // Acquire a scoped write lock via a transaction.
-  sync_api::WriteTransaction trans(share_handle());
+  sync_api::WriteTransaction trans(FROM_HERE, share_handle());
 
   // The given node's children got reordered. We need to reorder all the
   // children of the corresponding sync node.
diff --git a/chrome/browser/sync/glue/bookmark_model_associator.cc b/chrome/browser/sync/glue/bookmark_model_associator.cc
index 9aff7ad..5b46604 100644
--- a/chrome/browser/sync/glue/bookmark_model_associator.cc
+++ b/chrome/browser/sync/glue/bookmark_model_associator.cc
@@ -10,6 +10,7 @@
 #include "base/hash_tables.h"
 #include "base/message_loop.h"
 #include "base/task.h"
+#include "base/tracked.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/browser/bookmarks/bookmark_model.h"
 #include "chrome/browser/profiles/profile.h"
@@ -249,7 +250,7 @@ bool BookmarkModelAssociator::SyncModelHasUserCreatedNodes(bool* has_nodes) {
     has_synced_folder = false;
   }
 
-  sync_api::ReadTransaction trans(user_share_);
+  sync_api::ReadTransaction trans(FROM_HERE, user_share_);
 
   sync_api::ReadNode bookmark_bar_node(&trans);
   if (!bookmark_bar_node.InitByIdLookup(bookmark_bar_sync_id)) {
@@ -307,7 +308,7 @@ bool BookmarkModelAssociator::AssociateTaggedPermanentNode(
 
 bool BookmarkModelAssociator::GetSyncIdForTaggedNode(const std::string& tag,
                                                      int64* sync_id) {
-  sync_api::ReadTransaction trans(user_share_);
+  sync_api::ReadTransaction trans(FROM_HERE, user_share_);
   sync_api::ReadNode sync_node(&trans);
   if (!sync_node.InitByTagLookup(tag.c_str()))
     return false;
@@ -391,7 +392,7 @@ bool BookmarkModelAssociator::BuildAssociations() {
   dfs_stack.push(other_bookmarks_sync_id);
   dfs_stack.push(bookmark_bar_sync_id);
 
-  sync_api::WriteTransaction trans(user_share_);
+  sync_api::WriteTransaction trans(FROM_HERE, user_share_);
 
   while (!dfs_stack.empty()) {
     int64 sync_parent_id = dfs_stack.top();
@@ -478,7 +479,7 @@ void BookmarkModelAssociator::PersistAssociations() {
     return;
   }
 
-  sync_api::WriteTransaction trans(user_share_);
+  sync_api::WriteTransaction trans(FROM_HERE, user_share_);
   DirtyAssociationsSyncIds::iterator iter;
   for (iter = dirty_associations_sync_ids_.begin();
        iter != dirty_associations_sync_ids_.end();
@@ -542,7 +543,7 @@ bool BookmarkModelAssociator::LoadAssociations() {
   dfs_stack.push(other_bookmarks_id);
   dfs_stack.push(bookmark_bar_id);
 
-  sync_api::ReadTransaction trans(user_share_);
+  sync_api::ReadTransaction trans(FROM_HERE, user_share_);
 
   // Count total number of nodes in sync model so that we can compare that
   // with the total number of nodes in the bookmark model.
@@ -597,7 +598,7 @@ bool BookmarkModelAssociator::LoadAssociations() {
 
 bool BookmarkModelAssociator::CryptoReadyIfNecessary() {
   // We only access the cryptographer while holding a transaction.
-  sync_api::ReadTransaction trans(user_share_);
+  sync_api::ReadTransaction trans(FROM_HERE, user_share_);
   const syncable::ModelTypeSet& encrypted_types =
       sync_api::GetEncryptedTypes(&trans);
   return encrypted_types.count(syncable::BOOKMARKS) == 0 ||
diff --git a/chrome/browser/sync/glue/extension_model_associator.cc b/chrome/browser/sync/glue/extension_model_associator.cc
index 6bfbece..46594b6 100644
--- a/chrome/browser/sync/glue/extension_model_associator.cc
+++ b/chrome/browser/sync/glue/extension_model_associator.cc
@@ -5,6 +5,7 @@
 #include "chrome/browser/sync/glue/extension_model_associator.h"
 
 #include "base/logging.h"
+#include "base/tracked.h"
 #include "chrome/browser/extensions/extension_sync_data.h"
 #include "chrome/browser/sync/engine/syncapi.h"
 #include "chrome/browser/sync/glue/extension_sync_traits.h"
@@ -64,7 +65,7 @@ void ExtensionModelAssociator::AbortAssociation() {
 
 bool ExtensionModelAssociator::CryptoReadyIfNecessary() {
   // We only access the cryptographer while holding a transaction.
-  sync_api::ReadTransaction trans(user_share_);
+  sync_api::ReadTransaction trans(FROM_HERE, user_share_);
   const syncable::ModelTypeSet& encrypted_types =
       sync_api::GetEncryptedTypes(&trans);
   return encrypted_types.count(traits_.model_type) == 0 ||
diff --git a/chrome/browser/sync/glue/extension_sync.cc b/chrome/browser/sync/glue/extension_sync.cc
index 1b3b587..c6c19ec 100644
--- a/chrome/browser/sync/glue/extension_sync.cc
+++ b/chrome/browser/sync/glue/extension_sync.cc
@@ -7,6 +7,7 @@
 #include <utility>
 
 #include "base/logging.h"
+#include "base/tracked.h"
 #include "chrome/browser/extensions/extension_service.h"
 #include "chrome/browser/extensions/extension_sync_data.h"
 #include "chrome/browser/sync/engine/syncapi.h"
@@ -21,7 +22,7 @@ bool RootNodeHasChildren(const char* tag,
                          bool* has_children) {
   CHECK(has_children);
   *has_children = false;
-  sync_api::ReadTransaction trans(user_share);
+  sync_api::ReadTransaction trans(FROM_HERE, user_share);
   sync_api::ReadNode node(&trans);
   if (!node.InitByTagLookup(tag)) {
     LOG(ERROR) << "Root node with tag " << tag << " does not exist";
@@ -71,7 +72,7 @@ bool SlurpServerData(
     const ExtensionSpecificsGetter extension_specifics_getter,
     sync_api::UserShare* user_share,
     ExtensionDataMap* extension_data_map) {
-  sync_api::WriteTransaction trans(user_share);
+  sync_api::WriteTransaction trans(FROM_HERE, user_share);
   sync_api::ReadNode root(&trans);
   if (!root.InitByTagLookup(root_node_tag)) {
     LOG(ERROR) << GetRootNodeDoesNotExistError(root_node_tag);
@@ -154,7 +155,7 @@ bool FlushExtensionData(const ExtensionSyncTraits& traits,
                         const ExtensionDataMap& extension_data_map,
                         ExtensionServiceInterface* extension_service,
                         sync_api::UserShare* user_share) {
-  sync_api::WriteTransaction trans(user_share);
+  sync_api::WriteTransaction trans(FROM_HERE, user_share);
   sync_api::ReadNode root(&trans);
   if (!root.InitByTagLookup(traits.root_node_tag)) {
     LOG(ERROR) << GetRootNodeDoesNotExistError(traits.root_node_tag);
@@ -192,7 +193,7 @@ bool UpdateServerData(const ExtensionSyncTraits& traits,
     return false;
   }
 
-  sync_api::WriteTransaction trans(user_share);
+  sync_api::WriteTransaction trans(FROM_HERE, user_share);
   if (!UpdateServer(traits, data, &trans)) {
     *error =
         std::string("Could not update server data for extension ") + id;
@@ -205,7 +206,7 @@ bool UpdateServerData(const ExtensionSyncTraits& traits,
 void RemoveServerData(const ExtensionSyncTraits& traits,
                       const std::string& id,
                       sync_api::UserShare* user_share) {
-  sync_api::WriteTransaction trans(user_share);
+  sync_api::WriteTransaction trans(FROM_HERE, user_share);
   sync_api::WriteNode write_node(&trans);
   if (write_node.InitByClientTagLookup(traits.model_type, id)) {
     write_node.Remove();
diff --git a/chrome/browser/sync/glue/generic_change_processor.cc b/chrome/browser/sync/glue/generic_change_processor.cc
index 83c1736..976955e 100644
--- a/chrome/browser/sync/glue/generic_change_processor.cc
+++ b/chrome/browser/sync/glue/generic_change_processor.cc
@@ -4,6 +4,7 @@
 
 #include "chrome/browser/sync/glue/generic_change_processor.h"
 
+#include "base/tracked.h"
 #include "chrome/browser/sync/api/syncable_service.h"
 #include "chrome/browser/sync/api/sync_change.h"
 #include "chrome/browser/sync/engine/syncapi.h"
@@ -68,7 +69,7 @@ void GenericChangeProcessor::CommitChangesFromSyncModel() {
     return;
   if (syncer_changes_.empty())
     return;
-  local_service_->ProcessSyncChanges(syncer_changes_);
+  local_service_->ProcessSyncChanges(FROM_HERE, syncer_changes_);
   syncer_changes_.clear();
 }
 
@@ -76,7 +77,7 @@ bool GenericChangeProcessor::GetSyncDataForType(
     syncable::ModelType type,
     SyncDataList* current_sync_data) {
   std::string type_name = syncable::ModelTypeToString(type);
-  sync_api::ReadTransaction trans(share_handle());
+  sync_api::ReadTransaction trans(FROM_HERE, share_handle());
   sync_api::ReadNode root(&trans);
   if (!root.InitByTagLookup(syncable::ModelTypeToRootTag(type))) {
     LOG(ERROR) << "Server did not create the top-level " + type_name + " node."
@@ -99,8 +100,9 @@ bool GenericChangeProcessor::GetSyncDataForType(
 }
 
 void GenericChangeProcessor::ProcessSyncChanges(
+    const tracked_objects::Location& from_here,
     const SyncChangeList& list_of_changes) {
-  sync_api::WriteTransaction trans(share_handle());
+  sync_api::WriteTransaction trans(from_here, share_handle());
 
   for (SyncChangeList::const_iterator iter = list_of_changes.begin();
        iter != list_of_changes.end();
@@ -171,7 +173,7 @@ bool GenericChangeProcessor::SyncModelHasUserCreatedNodes(
   std::string err_str = "Server did not create the top-level " + type_name +
       " node. We might be running against an out-of-date server.";
   *has_nodes = false;
-  sync_api::ReadTransaction trans(share_handle());
+  sync_api::ReadTransaction trans(FROM_HERE, share_handle());
   sync_api::ReadNode type_root_node(&trans);
   if (!type_root_node.InitByTagLookup(syncable::ModelTypeToRootTag(type))) {
     LOG(ERROR) << err_str;
@@ -187,7 +189,7 @@ bool GenericChangeProcessor::SyncModelHasUserCreatedNodes(
 bool GenericChangeProcessor::CryptoReadyIfNecessary(syncable::ModelType type) {
   DCHECK_NE(type, syncable::UNSPECIFIED);
   // We only access the cryptographer while holding a transaction.
-  sync_api::ReadTransaction trans(share_handle());
+  sync_api::ReadTransaction trans(FROM_HERE, share_handle());
   const syncable::ModelTypeSet& encrypted_types =
       GetEncryptedTypes(&trans);
   return encrypted_types.count(type) == 0 ||
diff --git a/chrome/browser/sync/glue/generic_change_processor.h b/chrome/browser/sync/glue/generic_change_processor.h
index 0a7121f..d3176e5 100644
--- a/chrome/browser/sync/glue/generic_change_processor.h
+++ b/chrome/browser/sync/glue/generic_change_processor.h
@@ -45,7 +45,8 @@ class GenericChangeProcessor : public ChangeProcessor,
   virtual void CommitChangesFromSyncModel() OVERRIDE;
 
   // SyncChangeProcessor implementation.
-  virtual void ProcessSyncChanges(const SyncChangeList& change_list) OVERRIDE;
+  virtual void ProcessSyncChanges(const tracked_objects::Location& from_here,
+                                  const SyncChangeList& change_list) OVERRIDE;
 
   // Fills |current_sync_data| with all the syncer data for the specified type.
   virtual bool GetSyncDataForType(syncable::ModelType type,
diff --git a/chrome/browser/sync/glue/password_change_processor.cc b/chrome/browser/sync/glue/password_change_processor.cc
index a19b47e..67d9187 100644
--- a/chrome/browser/sync/glue/password_change_processor.cc
+++ b/chrome/browser/sync/glue/password_change_processor.cc
@@ -7,6 +7,7 @@
 #include <string>
 
 #include "base/string_util.h"
+#include "base/tracked.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/browser/password_manager/password_store.h"
 #include "chrome/browser/password_manager/password_store_change.h"
@@ -54,7 +55,7 @@ void PasswordChangeProcessor::Observe(NotificationType type,
 
   DCHECK(running());
 
-  sync_api::WriteTransaction trans(share_handle());
+  sync_api::WriteTransaction trans(FROM_HERE, share_handle());
 
   sync_api::ReadNode password_root(&trans);
   if (!password_root.InitByTagLookup(kPasswordTag)) {
diff --git a/chrome/browser/sync/glue/password_model_associator.cc b/chrome/browser/sync/glue/password_model_associator.cc
index baaffde..2931e94 100644
--- a/chrome/browser/sync/glue/password_model_associator.cc
+++ b/chrome/browser/sync/glue/password_model_associator.cc
@@ -7,6 +7,7 @@
 #include <set>
 
 #include "base/stl_util-inl.h"
+#include "base/tracked.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/browser/password_manager/password_store.h"
 #include "chrome/browser/sync/engine/syncapi.h"
@@ -60,7 +61,7 @@ bool PasswordModelAssociator::AssociateModels() {
   PasswordVector new_passwords;
   PasswordVector updated_passwords;
   {
-    sync_api::WriteTransaction trans(sync_service_->GetUserShare());
+    sync_api::WriteTransaction trans(FROM_HERE, sync_service_->GetUserShare());
     sync_api::ReadNode password_root(&trans);
     if (!password_root.InitByTagLookup(kPasswordTag)) {
       LOG(ERROR) << "Server did not create the top-level password node. We "
@@ -183,7 +184,7 @@ bool PasswordModelAssociator::SyncModelHasUserCreatedNodes(bool* has_nodes) {
                << "might be running against an out-of-date server.";
     return false;
   }
-  sync_api::ReadTransaction trans(sync_service_->GetUserShare());
+  sync_api::ReadTransaction trans(FROM_HERE, sync_service_->GetUserShare());
 
   sync_api::ReadNode password_node(&trans);
   if (!password_node.InitByIdLookup(password_sync_id)) {
@@ -206,7 +207,7 @@ void PasswordModelAssociator::AbortAssociation() {
 
 bool PasswordModelAssociator::CryptoReadyIfNecessary() {
   // We only access the cryptographer while holding a transaction.
-  sync_api::ReadTransaction trans(sync_service_->GetUserShare());
+  sync_api::ReadTransaction trans(FROM_HERE, sync_service_->GetUserShare());
   // We always encrypt passwords, so no need to check if encryption is enabled.
   return sync_service_->IsCryptographerReady(&trans);
 }
@@ -254,7 +255,7 @@ void PasswordModelAssociator::Disassociate(int64 sync_id) {
 
 bool PasswordModelAssociator::GetSyncIdForTaggedNode(const std::string& tag,
                                                      int64* sync_id) {
-  sync_api::ReadTransaction trans(sync_service_->GetUserShare());
+  sync_api::ReadTransaction trans(FROM_HERE, sync_service_->GetUserShare());
   sync_api::ReadNode sync_node(&trans);
   if (!sync_node.InitByTagLookup(tag.c_str()))
     return false;
diff --git a/chrome/browser/sync/glue/session_model_associator.cc b/chrome/browser/sync/glue/session_model_associator.cc
index 4f2812c..7d4eeb0 100644
--- a/chrome/browser/sync/glue/session_model_associator.cc
+++ b/chrome/browser/sync/glue/session_model_associator.cc
@@ -8,6 +8,7 @@
 #include <utility>
 
 #include "base/logging.h"
+#include "base/tracked.h"
 #include "chrome/browser/extensions/extension_tab_helper.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/sessions/restore_tab_helper.h"
@@ -70,7 +71,7 @@ bool SessionModelAssociator::SyncModelHasUserCreatedNodes(bool* has_nodes) {
   DCHECK(CalledOnValidThread());
   CHECK(has_nodes);
   *has_nodes = false;
-  sync_api::ReadTransaction trans(sync_service_->GetUserShare());
+  sync_api::ReadTransaction trans(FROM_HERE, sync_service_->GetUserShare());
   sync_api::ReadNode root(&trans);
   if (!root.InitByTagLookup(kSessionsTag)) {
     LOG(ERROR) << kNoSessionsFolderError;
@@ -89,7 +90,7 @@ int64 SessionModelAssociator::GetSyncIdFromChromeId(const size_t& id) {
 
 int64 SessionModelAssociator::GetSyncIdFromSessionTag(const std::string& tag) {
   DCHECK(CalledOnValidThread());
-  sync_api::ReadTransaction trans(sync_service_->GetUserShare());
+  sync_api::ReadTransaction trans(FROM_HERE, sync_service_->GetUserShare());
   sync_api::ReadNode node(&trans);
   if (!node.InitByClientTagLookup(syncable::SESSIONS, tag))
     return sync_api::kInvalidId;
@@ -160,7 +161,7 @@ void SessionModelAssociator::ReassociateWindows(bool reload_tabs) {
     }
   }
 
-  sync_api::WriteTransaction trans(sync_service_->GetUserShare());
+  sync_api::WriteTransaction trans(FROM_HERE, sync_service_->GetUserShare());
   sync_api::WriteNode header_node(&trans);
   if (!header_node.InitByIdLookup(local_session_syncid_)) {
     LOG(ERROR) << "Failed to load local session header node.";
@@ -228,7 +229,7 @@ void SessionModelAssociator::Associate(const TabContentsWrapper* tab,
   TabLinks t(sync_id, tab);
   tab_map_[session_id] = t;
 
-  sync_api::WriteTransaction trans(sync_service_->GetUserShare());
+  sync_api::WriteTransaction trans(FROM_HERE, sync_service_->GetUserShare());
   WriteTabContentsToSyncModel(*browser, *tab, sync_id, &trans);
 }
 
@@ -380,7 +381,7 @@ bool SessionModelAssociator::AssociateModels() {
   // 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_->GetUserShare());
+    sync_api::WriteTransaction trans(FROM_HERE, sync_service_->GetUserShare());
 
     sync_api::ReadNode root(&trans);
     if (!root.InitByTagLookup(kSessionsTag)) {
@@ -723,7 +724,7 @@ 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_->GetUserShare());
+    sync_api::WriteTransaction trans(FROM_HERE, sync_service_->GetUserShare());
     sync_api::ReadNode root(&trans);
     if (!root.InitByTagLookup(kSessionsTag)) {
       LOG(ERROR) << kNoSessionsFolderError;
@@ -855,7 +856,7 @@ void SessionModelAssociator::OnGotSession(
   sync_pb::SessionHeader* header_s = specifics.mutable_header();
   PopulateSessionSpecificsHeader(*windows, header_s);
 
-  sync_api::WriteTransaction trans(sync_service_->GetUserShare());
+  sync_api::WriteTransaction trans(FROM_HERE, sync_service_->GetUserShare());
   sync_api::ReadNode root(&trans);
   if (!root.InitByTagLookup(kSessionsTag)) {
     LOG(ERROR) << kNoSessionsFolderError;
@@ -929,7 +930,7 @@ bool SessionModelAssociator::SyncLocalWindowToSyncModel(
       return false;
     }
 
-    sync_api::WriteTransaction trans(sync_service_->GetUserShare());
+    sync_api::WriteTransaction trans(FROM_HERE, sync_service_->GetUserShare());
     if (!WriteSessionTabToSyncModel(*tab, id, &trans)) {
       return false;
     }
@@ -982,7 +983,7 @@ void SessionModelAssociator::PopulateSessionSpecificsTab(
 
 bool SessionModelAssociator::CryptoReadyIfNecessary() {
   // We only access the cryptographer while holding a transaction.
-  sync_api::ReadTransaction trans(sync_service_->GetUserShare());
+  sync_api::ReadTransaction trans(FROM_HERE, sync_service_->GetUserShare());
   syncable::ModelTypeSet encrypted_types;
   encrypted_types = sync_api::GetEncryptedTypes(&trans);
   return encrypted_types.count(syncable::SESSIONS) == 0 ||
diff --git a/chrome/browser/sync/glue/sync_backend_host.cc b/chrome/browser/sync/glue/sync_backend_host.cc
index 0576711..837077a 100644
--- a/chrome/browser/sync/glue/sync_backend_host.cc
+++ b/chrome/browser/sync/glue/sync_backend_host.cc
@@ -11,6 +11,7 @@
 #include "base/file_util.h"
 #include "base/task.h"
 #include "base/threading/thread_restrictions.h"
+#include "base/tracked.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/browser/net/gaia/token_service.h"
 #include "chrome/browser/prefs/pref_service.h"
@@ -312,7 +313,7 @@ void SyncBackendHost::SetAutofillMigrationDebugInfo(
 
 void SyncBackendHost::ConfigureAutofillMigration() {
   if (GetAutofillMigrationState() == syncable::NOT_DETERMINED) {
-    sync_api::ReadTransaction trans(GetUserShare());
+    sync_api::ReadTransaction trans(FROM_HERE, GetUserShare());
     sync_api::ReadNode autofil_root_node(&trans);
 
     // Check for the presence of autofill node.
diff --git a/chrome/browser/sync/glue/theme_change_processor.cc b/chrome/browser/sync/glue/theme_change_processor.cc
index a75b7eb..ace9931 100644
--- a/chrome/browser/sync/glue/theme_change_processor.cc
+++ b/chrome/browser/sync/glue/theme_change_processor.cc
@@ -5,6 +5,7 @@
 #include "chrome/browser/sync/glue/theme_change_processor.h"
 
 #include "base/logging.h"
+#include "base/tracked.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/sync/engine/syncapi.h"
 #include "chrome/browser/sync/glue/theme_util.h"
@@ -33,7 +34,7 @@ void ThemeChangeProcessor::Observe(NotificationType type,
   DCHECK(profile_);
   DCHECK(type == NotificationType::BROWSER_THEME_CHANGED);
 
-  sync_api::WriteTransaction trans(share_handle());
+  sync_api::WriteTransaction trans(FROM_HERE, share_handle());
   sync_api::WriteNode node(&trans);
   if (!node.InitByClientTagLookup(syncable::THEMES,
                                   kCurrentThemeClientTag)) {
diff --git a/chrome/browser/sync/glue/theme_model_associator.cc b/chrome/browser/sync/glue/theme_model_associator.cc
index 5c70068..e53b021 100644
--- a/chrome/browser/sync/glue/theme_model_associator.cc
+++ b/chrome/browser/sync/glue/theme_model_associator.cc
@@ -6,6 +6,7 @@
 
 #include "base/basictypes.h"
 #include "base/logging.h"
+#include "base/tracked.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/browser/sync/engine/syncapi.h"
 #include "chrome/browser/sync/glue/sync_backend_host.h"
@@ -35,7 +36,7 @@ ThemeModelAssociator::ThemeModelAssociator(
 ThemeModelAssociator::~ThemeModelAssociator() {}
 
 bool ThemeModelAssociator::AssociateModels() {
-  sync_api::WriteTransaction trans(sync_service_->GetUserShare());
+  sync_api::WriteTransaction trans(FROM_HERE, sync_service_->GetUserShare());
   sync_api::ReadNode root(&trans);
   if (!root.InitByTagLookup(kThemesTag)) {
     LOG(ERROR) << kNoThemesFolderError;
@@ -81,7 +82,7 @@ bool ThemeModelAssociator::DisassociateModels() {
 bool ThemeModelAssociator::SyncModelHasUserCreatedNodes(bool* has_nodes) {
   DCHECK(has_nodes);
   *has_nodes = false;
-  sync_api::ReadTransaction trans(sync_service_->GetUserShare());
+  sync_api::ReadTransaction trans(FROM_HERE, sync_service_->GetUserShare());
   sync_api::ReadNode root(&trans);
   if (!root.InitByTagLookup(kThemesTag)) {
     LOG(ERROR) << kNoThemesFolderError;
@@ -95,7 +96,7 @@ bool ThemeModelAssociator::SyncModelHasUserCreatedNodes(bool* has_nodes) {
 
 bool ThemeModelAssociator::CryptoReadyIfNecessary() {
   // We only access the cryptographer while holding a transaction.
-  sync_api::ReadTransaction trans(sync_service_->GetUserShare());
+  sync_api::ReadTransaction trans(FROM_HERE, sync_service_->GetUserShare());
   syncable::ModelTypeSet encrypted_types;
   encrypted_types = sync_api::GetEncryptedTypes(&trans);
   return encrypted_types.count(syncable::THEMES) == 0 ||
diff --git a/chrome/browser/sync/glue/typed_url_change_processor.cc b/chrome/browser/sync/glue/typed_url_change_processor.cc
index 13a202d..e269814 100644
--- a/chrome/browser/sync/glue/typed_url_change_processor.cc
+++ b/chrome/browser/sync/glue/typed_url_change_processor.cc
@@ -5,6 +5,7 @@
 #include "chrome/browser/sync/glue/typed_url_change_processor.h"
 
 #include "base/string_util.h"
+#include "base/tracked.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/browser/history/history_backend.h"
 #include "chrome/browser/history/history_notifications.h"
@@ -84,7 +85,7 @@ void TypedUrlChangeProcessor::HandleURLsModified(
     }
   }
 
-  sync_api::WriteTransaction trans(share_handle());
+  sync_api::WriteTransaction trans(FROM_HERE, share_handle());
 
   sync_api::ReadNode typed_url_root(&trans);
   if (!typed_url_root.InitByTagLookup(kTypedUrlTag)) {
@@ -125,7 +126,7 @@ void TypedUrlChangeProcessor::HandleURLsModified(
 
 void TypedUrlChangeProcessor::HandleURLsDeleted(
     history::URLsDeletedDetails* details) {
-  sync_api::WriteTransaction trans(share_handle());
+  sync_api::WriteTransaction trans(FROM_HERE, share_handle());
 
   if (details->all_history) {
     if (!model_associator_->DeleteAllNodes(&trans)) {
@@ -164,7 +165,7 @@ void TypedUrlChangeProcessor::HandleURLsVisited(
     return;
   }
 
-  sync_api::WriteTransaction trans(share_handle());
+  sync_api::WriteTransaction trans(FROM_HERE, share_handle());
   std::string tag = details->row.url().spec();
   sync_api::WriteNode update_node(&trans);
   if (!update_node.InitByClientTagLookup(syncable::TYPED_URLS, tag)) {
diff --git a/chrome/browser/sync/glue/typed_url_model_associator.cc b/chrome/browser/sync/glue/typed_url_model_associator.cc
index 50758a7..337a7c4 100644
--- a/chrome/browser/sync/glue/typed_url_model_associator.cc
+++ b/chrome/browser/sync/glue/typed_url_model_associator.cc
@@ -7,6 +7,7 @@
 #include <algorithm>
 #include <set>
 
+#include "base/tracked.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/browser/history/history_backend.h"
 #include "chrome/browser/sync/engine/syncapi.h"
@@ -68,7 +69,7 @@ bool TypedUrlModelAssociator::AssociateModels() {
   TypedUrlUpdateVector updated_urls;
 
   {
-    sync_api::WriteTransaction trans(sync_service_->GetUserShare());
+    sync_api::WriteTransaction trans(FROM_HERE, sync_service_->GetUserShare());
     sync_api::ReadNode typed_url_root(&trans);
     if (!typed_url_root.InitByTagLookup(kTypedUrlTag)) {
       LOG(ERROR) << "Server did not create the top-level typed_url node. We "
@@ -265,7 +266,7 @@ bool TypedUrlModelAssociator::SyncModelHasUserCreatedNodes(bool* has_nodes) {
                << "might be running against an out-of-date server.";
     return false;
   }
-  sync_api::ReadTransaction trans(sync_service_->GetUserShare());
+  sync_api::ReadTransaction trans(FROM_HERE, sync_service_->GetUserShare());
 
   sync_api::ReadNode typed_url_node(&trans);
   if (!typed_url_node.InitByIdLookup(typed_url_sync_id)) {
@@ -327,7 +328,7 @@ void TypedUrlModelAssociator::Disassociate(int64 sync_id) {
 
 bool TypedUrlModelAssociator::GetSyncIdForTaggedNode(const std::string& tag,
                                                      int64* sync_id) {
-  sync_api::ReadTransaction trans(sync_service_->GetUserShare());
+  sync_api::ReadTransaction trans(FROM_HERE, sync_service_->GetUserShare());
   sync_api::ReadNode sync_node(&trans);
   if (!sync_node.InitByTagLookup(tag.c_str()))
     return false;
@@ -577,7 +578,7 @@ void TypedUrlModelAssociator::UpdateURLRowFromTypedUrlSpecifics(
 
 bool TypedUrlModelAssociator::CryptoReadyIfNecessary() {
   // We only access the cryptographer while holding a transaction.
-  sync_api::ReadTransaction trans(sync_service_->GetUserShare());
+  sync_api::ReadTransaction trans(FROM_HERE, sync_service_->GetUserShare());
   syncable::ModelTypeSet encrypted_types;
   encrypted_types = sync_api::GetEncryptedTypes(&trans);
   return encrypted_types.count(syncable::TYPED_URLS) == 0 ||
diff --git a/chrome/browser/sync/js_sync_manager_observer_unittest.cc b/chrome/browser/sync/js_sync_manager_observer_unittest.cc
index 08d38f4..e71c059 100644
--- a/chrome/browser/sync/js_sync_manager_observer_unittest.cc
+++ b/chrome/browser/sync/js_sync_manager_observer_unittest.cc
@@ -7,6 +7,7 @@
 #include <cstddef>
 
 #include "base/basictypes.h"
+#include "base/tracked.h"
 #include "base/values.h"
 #include "chrome/browser/sync/engine/syncapi.h"
 #include "chrome/browser/sync/js_arg_list.h"
@@ -222,7 +223,7 @@ namespace {
 // Makes a node of the given model type.  Returns the id of the
 // newly-created node.
 int64 MakeNode(sync_api::UserShare* share, syncable::ModelType model_type) {
-  sync_api::WriteTransaction trans(share);
+  sync_api::WriteTransaction trans(FROM_HERE, share);
   sync_api::ReadNode root_node(&trans);
   root_node.InitByRootLookup();
   sync_api::WriteNode node(&trans);
@@ -264,7 +265,7 @@ TEST_F(JsSyncManagerObserverTest, OnChangesApplied) {
         break;
     }
     {
-      sync_api::ReadTransaction trans(test_user_share.user_share());
+      sync_api::ReadTransaction trans(FROM_HERE, test_user_share.user_share());
       sync_api::ReadNode node(&trans);
       EXPECT_TRUE(node.InitByIdLookup(changes[i].id));
       changes[i].specifics = node.GetEntry()->Get(syncable::SPECIFICS);
@@ -285,7 +286,7 @@ TEST_F(JsSyncManagerObserverTest, OnChangesApplied) {
     ListValue* expected_changes = new ListValue();
     expected_details.Set("changes", expected_changes);
     for (int j = i; j < syncable::MODEL_TYPE_COUNT; ++j) {
-      sync_api::ReadTransaction trans(test_user_share.user_share());
+      sync_api::ReadTransaction trans(FROM_HERE, test_user_share.user_share());
       expected_changes->Append(changes[j].ToValue(&trans));
     }
     EXPECT_CALL(mock_router_,
@@ -296,7 +297,7 @@ TEST_F(JsSyncManagerObserverTest, OnChangesApplied) {
   // Fire OnChangesApplied() for each data type.
   for (int i = syncable::AUTOFILL_PROFILE;
        i < syncable::MODEL_TYPE_COUNT; ++i) {
-    sync_api::ReadTransaction trans(test_user_share.user_share());
+    sync_api::ReadTransaction trans(FROM_HERE, test_user_share.user_share());
     sync_manager_observer_.OnChangesApplied(syncable::ModelTypeFromInt(i),
                                             &trans, &changes[i],
                                             syncable::MODEL_TYPE_COUNT - i);
diff --git a/chrome/browser/sync/profile_sync_service_autofill_unittest.cc b/chrome/browser/sync/profile_sync_service_autofill_unittest.cc
index b6d966d..4e13929 100644
--- a/chrome/browser/sync/profile_sync_service_autofill_unittest.cc
+++ b/chrome/browser/sync/profile_sync_service_autofill_unittest.cc
@@ -333,7 +333,7 @@ class ProfileSyncServiceAutofillTest : public AbstractProfileSyncServiceTest {
   }
 
   bool AddAutofillSyncNode(const AutofillEntry& entry) {
-    sync_api::WriteTransaction trans(service_->GetUserShare());
+    sync_api::WriteTransaction trans(FROM_HERE, service_->GetUserShare());
     sync_api::ReadNode autofill_root(&trans);
     if (!autofill_root.InitByTagLookup(browser_sync::kAutofillTag))
       return false;
@@ -349,7 +349,7 @@ class ProfileSyncServiceAutofillTest : public AbstractProfileSyncServiceTest {
   }
 
   bool AddAutofillSyncNode(const AutofillProfile& profile) {
-    sync_api::WriteTransaction trans(service_->GetUserShare());
+    sync_api::WriteTransaction trans(FROM_HERE, service_->GetUserShare());
     sync_api::ReadNode autofill_root(&trans);
     if (!autofill_root.InitByTagLookup(browser_sync::kAutofillProfileTag))
       return false;
@@ -364,7 +364,7 @@ class ProfileSyncServiceAutofillTest : public AbstractProfileSyncServiceTest {
 
   bool GetAutofillEntriesFromSyncDB(std::vector<AutofillEntry>* entries,
                                     std::vector<AutofillProfile>* profiles) {
-    sync_api::ReadTransaction trans(service_->GetUserShare());
+    sync_api::ReadTransaction trans(FROM_HERE, service_->GetUserShare());
     sync_api::ReadNode autofill_root(&trans);
     if (!autofill_root.InitByTagLookup(browser_sync::kAutofillTag))
       return false;
@@ -401,7 +401,7 @@ class ProfileSyncServiceAutofillTest : public AbstractProfileSyncServiceTest {
 
   bool GetAutofillProfilesFromSyncDBUnderProfileNode(
       std::vector<AutofillProfile>* profiles) {
-    sync_api::ReadTransaction trans(service_->GetUserShare());
+    sync_api::ReadTransaction trans(FROM_HERE, service_->GetUserShare());
     sync_api::ReadNode autofill_root(&trans);
     if (!autofill_root.InitByTagLookup(browser_sync::kAutofillProfileTag))
       return false;
@@ -491,11 +491,11 @@ class AddAutofillTask : public Task {
 static const bool kLoggingInfo = true;
 class WriteTransactionTest: public WriteTransaction {
  public:
-  WriteTransactionTest(const syncable::ScopedDirLookup& directory,
+  WriteTransactionTest(const tracked_objects::Location& from_here,
                        WriterTag writer,
-                       const tracked_objects::Location& from_here,
+                       const syncable::ScopedDirLookup& directory,
                        scoped_ptr<WaitableEvent> *wait_for_syncapi)
-      : WriteTransaction(directory, writer, from_here),
+      : WriteTransaction(from_here, writer, directory),
         wait_for_syncapi_(wait_for_syncapi) { }
 
   virtual void NotifyTransactionComplete(syncable::ModelTypeBitSet types) {
@@ -553,7 +553,7 @@ class FakeServerUpdater: public base::RefCountedThreadSafe<FakeServerUpdater> {
       (*wait_for_start_)->Signal();
 
       // Create write transaction.
-      WriteTransactionTest trans(dir, UNITTEST, FROM_HERE,
+      WriteTransactionTest trans(FROM_HERE, UNITTEST, dir,
                                  wait_for_syncapi_);
 
       // Create actual entry based on autofill protobuf information.
diff --git a/chrome/browser/sync/profile_sync_service_bookmark_unittest.cc b/chrome/browser/sync/profile_sync_service_bookmark_unittest.cc
index 39e6d74..3bdae6e 100644
--- a/chrome/browser/sync/profile_sync_service_bookmark_unittest.cc
+++ b/chrome/browser/sync/profile_sync_service_bookmark_unittest.cc
@@ -17,6 +17,7 @@
 #include "base/string16.h"
 #include "base/string_number_conversions.h"
 #include "base/string_util.h"
+#include "base/tracked.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/browser/bookmarks/bookmark_model.h"
 #include "chrome/browser/sync/abstract_profile_sync_service_test.h"
@@ -64,7 +65,7 @@ class TestBookmarkModelAssociator : public BookmarkModelAssociator {
     bool root_exists = false;
     syncable::ModelType type = model_type();
     {
-      sync_api::WriteTransaction trans(user_share_);
+      sync_api::WriteTransaction trans(FROM_HERE, user_share_);
       sync_api::ReadNode uber_root(&trans);
       uber_root.InitByRootLookup();
 
@@ -82,7 +83,7 @@ class TestBookmarkModelAssociator : public BookmarkModelAssociator {
         return false;
     }
 
-    sync_api::WriteTransaction trans(user_share_);
+    sync_api::WriteTransaction trans(FROM_HERE, user_share_);
     sync_api::ReadNode root(&trans);
     EXPECT_TRUE(root.InitByTagLookup(
         ProfileSyncServiceTestHelper::GetTagForType(type)));
@@ -403,7 +404,7 @@ class ProfileSyncServiceBookmarkTest : public testing::Test {
   }
 
   void ExpectSyncerNodeMatching(const BookmarkNode* bnode) {
-    sync_api::ReadTransaction trans(test_user_share_.user_share());
+    sync_api::ReadTransaction trans(FROM_HERE, test_user_share_.user_share());
     ExpectSyncerNodeMatching(&trans, bnode);
   }
 
@@ -483,7 +484,7 @@ class ProfileSyncServiceBookmarkTest : public testing::Test {
   }
 
   void ExpectModelMatch() {
-    sync_api::ReadTransaction trans(test_user_share_.user_share());
+    sync_api::ReadTransaction trans(FROM_HERE, test_user_share_.user_share());
     ExpectModelMatch(&trans);
   }
 
@@ -593,7 +594,7 @@ TEST_F(ProfileSyncServiceBookmarkTest, ServerChangeProcessing) {
   LoadBookmarkModel(DELETE_EXISTING_STORAGE, DONT_SAVE_TO_STORAGE);
   StartSync();
 
-  sync_api::WriteTransaction trans(test_user_share_.user_share());
+  sync_api::WriteTransaction trans(FROM_HERE, test_user_share_.user_share());
 
   FakeServerChange adds(&trans);
   int64 f1 = adds.AddFolder(L"Server Folder B", bookmark_bar_id(), 0);
@@ -690,7 +691,7 @@ TEST_F(ProfileSyncServiceBookmarkTest, ServerChangeRequiringFosterParent) {
   LoadBookmarkModel(DELETE_EXISTING_STORAGE, DONT_SAVE_TO_STORAGE);
   StartSync();
 
-  sync_api::WriteTransaction trans(test_user_share_.user_share());
+  sync_api::WriteTransaction trans(FROM_HERE, test_user_share_.user_share());
 
   // Stress the immediate children of other_node because that's where
   // ApplyModelChanges puts a temporary foster parent node.
@@ -739,7 +740,7 @@ TEST_F(ProfileSyncServiceBookmarkTest, ServerChangeWithNonCanonicalURL) {
   StartSync();
 
   {
-    sync_api::WriteTransaction trans(test_user_share_.user_share());
+    sync_api::WriteTransaction trans(FROM_HERE, test_user_share_.user_share());
 
     FakeServerChange adds(&trans);
     std::string url("http://dev.chromium.org");
@@ -770,7 +771,7 @@ TEST_F(ProfileSyncServiceBookmarkTest, DISABLED_ServerChangeWithInvalidURL) {
 
   int child_count = 0;
   {
-    sync_api::WriteTransaction trans(test_user_share_.user_share());
+    sync_api::WriteTransaction trans(FROM_HERE, test_user_share_.user_share());
 
     FakeServerChange adds(&trans);
     std::string url("x");
@@ -887,7 +888,7 @@ TEST_F(ProfileSyncServiceBookmarkTest, UnrecoverableErrorSuspendsService) {
   // updating the ProfileSyncService state.  This should introduce
   // inconsistency between the two models.
   {
-    sync_api::WriteTransaction trans(test_user_share_.user_share());
+    sync_api::WriteTransaction trans(FROM_HERE, test_user_share_.user_share());
     sync_api::WriteNode sync_node(&trans);
     ASSERT_TRUE(InitSyncNodeFromChromeNode(node, &sync_node));
     sync_node.Remove();
diff --git a/chrome/browser/sync/profile_sync_service_password_unittest.cc b/chrome/browser/sync/profile_sync_service_password_unittest.cc
index 072bb36..0433b67 100644
--- a/chrome/browser/sync/profile_sync_service_password_unittest.cc
+++ b/chrome/browser/sync/profile_sync_service_password_unittest.cc
@@ -10,6 +10,7 @@
 #include "base/task.h"
 #include "base/test/test_timeouts.h"
 #include "base/time.h"
+#include "base/tracked.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/browser/password_manager/password_store.h"
 #include "chrome/browser/prefs/pref_service.h"
@@ -86,7 +87,8 @@ ACTION_P3(MakePasswordSyncComponents, service, ps, dtc) {
 ACTION_P(AcquireSyncTransaction, password_test_service) {
   // Check to make sure we can aquire a transaction (will crash if a transaction
   // is already held by this thread, deadlock if held by another thread).
-  sync_api::WriteTransaction trans(password_test_service->GetUserShare());
+  sync_api::WriteTransaction trans(
+      FROM_HERE, password_test_service->GetUserShare());
   VLOG(1) << "Sync transaction acquired.";
 }
 
@@ -238,7 +240,7 @@ class ProfileSyncServicePasswordTest : public AbstractProfileSyncServiceTest {
   }
 
   void AddPasswordSyncNode(const PasswordForm& entry) {
-    sync_api::WriteTransaction trans(service_->GetUserShare());
+    sync_api::WriteTransaction trans(FROM_HERE, service_->GetUserShare());
     sync_api::ReadNode password_root(&trans);
     ASSERT_TRUE(password_root.InitByTagLookup(browser_sync::kPasswordTag));
 
@@ -251,7 +253,7 @@ class ProfileSyncServicePasswordTest : public AbstractProfileSyncServiceTest {
   }
 
   void GetPasswordEntriesFromSyncDB(std::vector<PasswordForm>* entries) {
-    sync_api::ReadTransaction trans(service_->GetUserShare());
+    sync_api::ReadTransaction trans(FROM_HERE, service_->GetUserShare());
     sync_api::ReadNode password_root(&trans);
     ASSERT_TRUE(password_root.InitByTagLookup(browser_sync::kPasswordTag));
 
diff --git a/chrome/browser/sync/profile_sync_service_preference_unittest.cc b/chrome/browser/sync/profile_sync_service_preference_unittest.cc
index b6cfd53..436f213 100644
--- a/chrome/browser/sync/profile_sync_service_preference_unittest.cc
+++ b/chrome/browser/sync/profile_sync_service_preference_unittest.cc
@@ -9,6 +9,7 @@
 #include "base/stl_util-inl.h"
 #include "base/string_piece.h"
 #include "base/task.h"
+#include "base/tracked.h"
 #include "chrome/browser/prefs/pref_model_associator.h"
 #include "chrome/browser/prefs/scoped_user_pref_update.h"
 #include "chrome/browser/sync/abstract_profile_sync_service_test.h"
@@ -124,7 +125,7 @@ class ProfileSyncServicePreferenceTest
 
   // Caller gets ownership of the returned value.
   const Value* GetSyncedValue(const std::string& name) {
-    sync_api::ReadTransaction trans(service_->GetUserShare());
+    sync_api::ReadTransaction trans(FROM_HERE, service_->GetUserShare());
     sync_api::ReadNode node(&trans);
 
     if (!node.InitByClientTagLookup(syncable::PREFERENCES, name))
@@ -151,7 +152,7 @@ class ProfileSyncServicePreferenceTest
   }
 
   int64 SetSyncedValue(const std::string& name, const Value& value) {
-    sync_api::WriteTransaction trans(service_->GetUserShare());
+    sync_api::WriteTransaction trans(FROM_HERE, service_->GetUserShare());
     sync_api::ReadNode root(&trans);
     if (!root.InitByTagLookup(
         syncable::ModelTypeToRootTag(syncable::PREFERENCES))) {
@@ -385,7 +386,7 @@ TEST_F(ProfileSyncServicePreferenceTest, UpdatedSyncNodeActionUpdate) {
   scoped_ptr<SyncManager::ChangeRecord> record(MakeChangeRecord(
       node_id, SyncManager::ChangeRecord::ACTION_UPDATE));
   {
-    sync_api::WriteTransaction trans(service_->GetUserShare());
+    sync_api::WriteTransaction trans(FROM_HERE, service_->GetUserShare());
     change_processor_->ApplyChangesFromSyncModel(&trans, record.get(), 1);
   }
   change_processor_->CommitChangesFromSyncModel();
@@ -405,7 +406,7 @@ TEST_F(ProfileSyncServicePreferenceTest, UpdatedSyncNodeActionAdd) {
   scoped_ptr<SyncManager::ChangeRecord> record(MakeChangeRecord(
       node_id, SyncManager::ChangeRecord::ACTION_ADD));
   {
-    sync_api::WriteTransaction trans(service_->GetUserShare());
+    sync_api::WriteTransaction trans(FROM_HERE, service_->GetUserShare());
     change_processor_->ApplyChangesFromSyncModel(&trans, record.get(), 1);
   }
   change_processor_->CommitChangesFromSyncModel();
@@ -427,7 +428,7 @@ TEST_F(ProfileSyncServicePreferenceTest, UpdatedSyncNodeUnknownPreference) {
   scoped_ptr<SyncManager::ChangeRecord> record(MakeChangeRecord(
       node_id, SyncManager::ChangeRecord::ACTION_UPDATE));
   {
-    sync_api::WriteTransaction trans(service_->GetUserShare());
+    sync_api::WriteTransaction trans(FROM_HERE, service_->GetUserShare());
     change_processor_->ApplyChangesFromSyncModel(&trans, record.get(), 1);
   }
   change_processor_->CommitChangesFromSyncModel();
@@ -460,7 +461,7 @@ TEST_F(ProfileSyncServicePreferenceTest, ManagedPreferences) {
   scoped_ptr<SyncManager::ChangeRecord> record(MakeChangeRecord(
       node_id, SyncManager::ChangeRecord::ACTION_UPDATE));
   {
-    sync_api::WriteTransaction trans(service_->GetUserShare());
+    sync_api::WriteTransaction trans(FROM_HERE, service_->GetUserShare());
     change_processor_->ApplyChangesFromSyncModel(&trans, record.get(), 1);
   }
   change_processor_->CommitChangesFromSyncModel();
@@ -500,7 +501,7 @@ TEST_F(ProfileSyncServicePreferenceTest, DynamicManagedPreferences) {
   scoped_ptr<SyncManager::ChangeRecord> record(MakeChangeRecord(
       node_id, SyncManager::ChangeRecord::ACTION_ADD));
   {
-    sync_api::WriteTransaction trans(service_->GetUserShare());
+    sync_api::WriteTransaction trans(FROM_HERE, service_->GetUserShare());
     change_processor_->ApplyChangesFromSyncModel(&trans, record.get(), 1);
   }
   change_processor_->CommitChangesFromSyncModel();
diff --git a/chrome/browser/sync/profile_sync_service_session_unittest.cc b/chrome/browser/sync/profile_sync_service_session_unittest.cc
index dac1129..590b2ad 100644
--- a/chrome/browser/sync/profile_sync_service_session_unittest.cc
+++ b/chrome/browser/sync/profile_sync_service_session_unittest.cc
@@ -10,6 +10,7 @@
 #include "base/scoped_temp_dir.h"
 #include "base/stl_util-inl.h"
 #include "base/task.h"
+#include "base/tracked.h"
 #include "chrome/browser/sessions/session_service.h"
 #include "chrome/browser/sessions/session_service_factory.h"
 #include "chrome/browser/sessions/session_service_test_helper.h"
@@ -191,7 +192,7 @@ TEST_F(ProfileSyncServiceSessionTest, WriteSessionToNode) {
   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_->GetUserShare());
+  sync_api::ReadTransaction trans(FROM_HERE, sync_service_->GetUserShare());
   sync_api::ReadNode node(&trans);
   ASSERT_TRUE(node.InitByClientTagLookup(syncable::SESSIONS,
       machine_tag));
@@ -343,7 +344,7 @@ TEST_F(ProfileSyncServiceSessionTest, UpdatedSyncNodeActionUpdate) {
   record->id = node_id;
   ASSERT_FALSE(notified_of_update_);
   {
-    sync_api::WriteTransaction trans(sync_service_->GetUserShare());
+    sync_api::WriteTransaction trans(FROM_HERE, sync_service_->GetUserShare());
     change_processor_->ApplyChangesFromSyncModel(&trans, record.get(), 1);
   }
   ASSERT_TRUE(notified_of_update_);
@@ -362,7 +363,7 @@ TEST_F(ProfileSyncServiceSessionTest, UpdatedSyncNodeActionAdd) {
   record->id = node_id;
   ASSERT_FALSE(notified_of_update_);
   {
-    sync_api::WriteTransaction trans(sync_service_->GetUserShare());
+    sync_api::WriteTransaction trans(FROM_HERE, sync_service_->GetUserShare());
     change_processor_->ApplyChangesFromSyncModel(&trans, record.get(), 1);
   }
   ASSERT_TRUE(notified_of_update_);
@@ -381,7 +382,7 @@ TEST_F(ProfileSyncServiceSessionTest, UpdatedSyncNodeActionDelete) {
   record->id = node_id;
   ASSERT_FALSE(notified_of_update_);
   {
-    sync_api::WriteTransaction trans(sync_service_->GetUserShare());
+    sync_api::WriteTransaction trans(FROM_HERE, sync_service_->GetUserShare());
     change_processor_->ApplyChangesFromSyncModel(&trans, record.get(), 1);
   }
   ASSERT_TRUE(notified_of_update_);
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 417036c..13b7bc5 100644
--- a/chrome/browser/sync/profile_sync_service_typed_url_unittest.cc
+++ b/chrome/browser/sync/profile_sync_service_typed_url_unittest.cc
@@ -10,6 +10,7 @@
 #include "base/string16.h"
 #include "base/threading/thread.h"
 #include "base/time.h"
+#include "base/tracked.h"
 #include "chrome/browser/history/history_backend.h"
 #include "chrome/browser/history/history_notifications.h"
 #include "chrome/browser/history/history_types.h"
@@ -196,7 +197,7 @@ class ProfileSyncServiceTypedUrlTest : public AbstractProfileSyncServiceTest {
 
   void AddTypedUrlSyncNode(const history::URLRow& url,
                            const history::VisitVector& visits) {
-    sync_api::WriteTransaction trans(service_->GetUserShare());
+    sync_api::WriteTransaction trans(FROM_HERE, service_->GetUserShare());
     sync_api::ReadNode typed_url_root(&trans);
     ASSERT_TRUE(typed_url_root.InitByTagLookup(browser_sync::kTypedUrlTag));
 
@@ -209,7 +210,7 @@ class ProfileSyncServiceTypedUrlTest : public AbstractProfileSyncServiceTest {
   }
 
   void GetTypedUrlsFromSyncDB(std::vector<history::URLRow>* urls) {
-    sync_api::ReadTransaction trans(service_->GetUserShare());
+    sync_api::ReadTransaction trans(FROM_HERE, service_->GetUserShare());
     sync_api::ReadNode typed_url_root(&trans);
     if (!typed_url_root.InitByTagLookup(browser_sync::kTypedUrlTag))
       return;
diff --git a/chrome/browser/sync/sessions/sync_session_unittest.cc b/chrome/browser/sync/sessions/sync_session_unittest.cc
index dc9ad8a..b6cbe81 100644
--- a/chrome/browser/sync/sessions/sync_session_unittest.cc
+++ b/chrome/browser/sync/sessions/sync_session_unittest.cc
@@ -124,7 +124,7 @@ TEST_F(SyncSessionTest, SetWriteTransaction) {
   scoped_ptr<SyncSession> session(MakeSession());
   EXPECT_TRUE(NULL == session->write_transaction());
   {
-    WriteTransaction trans(dir, syncable::UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, syncable::UNITTEST, dir);
     sessions::ScopedSetSessionWriteTransaction set_trans(session.get(), &trans);
     EXPECT_TRUE(&trans == session->write_transaction());
   }
diff --git a/chrome/browser/sync/syncable/syncable.cc b/chrome/browser/sync/syncable/syncable.cc
index 039ad41..43fbec6 100644
--- a/chrome/browser/sync/syncable/syncable.cc
+++ b/chrome/browser/sync/syncable/syncable.cc
@@ -654,7 +654,7 @@ bool Directory::SafeToPurgeFromMemory(const EntryKernel* const entry) const {
 }
 
 void Directory::TakeSnapshotForSaveChanges(SaveChangesSnapshot* snapshot) {
-  ReadTransaction trans(this, FROM_HERE);
+  ReadTransaction trans(FROM_HERE, this);
   ScopedKernelLock lock(this);
   // Deep copy dirty entries from kernel_->metahandles_index into snapshot and
   // clear dirty flags.
@@ -712,7 +712,7 @@ bool Directory::SaveChanges() {
 
 void Directory::VacuumAfterSaveChanges(const SaveChangesSnapshot& snapshot) {
   // Need a write transaction as we are about to permanently purge entries.
-  WriteTransaction trans(this, VACUUM_AFTER_SAVE, FROM_HERE);
+  WriteTransaction trans(FROM_HERE, VACUUM_AFTER_SAVE, this);
   ScopedKernelLock lock(this);
   kernel_->flushed_metahandles.Push(0);  // Begin flush marker
   // Now drop everything we can out of memory.
@@ -753,7 +753,7 @@ void Directory::PurgeEntriesWithTypeIn(const std::set<ModelType>& types) {
     return;
 
   {
-    WriteTransaction trans(this, PURGE_ENTRIES, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, PURGE_ENTRIES, this);
     {
       ScopedKernelLock lock(this);
       MetahandlesIndex::iterator it = kernel_->metahandles_index->begin();
@@ -1199,11 +1199,12 @@ void BaseTransaction::Lock() {
       << elapsed.InSecondsF() << " seconds.";
 }
 
-BaseTransaction::BaseTransaction(
-    Directory* directory, const char* name,
-    const tracked_objects::Location& from_here, WriterTag writer)
-  : directory_(directory), dirkernel_(directory->kernel_), name_(name),
-    from_here_(from_here), writer_(writer) {
+BaseTransaction::BaseTransaction(const tracked_objects::Location& from_here,
+                                 const char* name,
+                                 WriterTag writer,
+                                 Directory* directory)
+    : from_here_(from_here), name_(name), writer_(writer),
+      directory_(directory), dirkernel_(directory->kernel_) {
   dirkernel_->observers->Notify(
       &TransactionObserver::OnTransactionStart, from_here_, writer_);
   Lock();
@@ -1272,31 +1273,31 @@ void BaseTransaction::NotifyTransactionComplete(
 
 #undef VLOG_LOC_STREAM
 
-ReadTransaction::ReadTransaction(Directory* directory,
-                                 const tracked_objects::Location& location)
-  : BaseTransaction(directory, "Read", location, INVALID) {
+ReadTransaction::ReadTransaction(const tracked_objects::Location& location,
+                                 Directory* directory)
+    : BaseTransaction(location, "Read", INVALID, directory) {
 }
 
-ReadTransaction::ReadTransaction(const ScopedDirLookup& scoped_dir,
-                                 const tracked_objects::Location& location)
-  : BaseTransaction(scoped_dir.operator -> (), "Read", location, INVALID) {
+ReadTransaction::ReadTransaction(const tracked_objects::Location& location,
+                                 const ScopedDirLookup& scoped_dir)
+    : BaseTransaction(location, "Read", INVALID, scoped_dir.operator->()) {
 }
 
 ReadTransaction::~ReadTransaction() {
   UnlockAndLog(NULL);
 }
 
-WriteTransaction::WriteTransaction(Directory* directory, WriterTag writer,
-                                   const tracked_objects::Location& location)
-  : BaseTransaction(directory, "Write", location, writer),
-    originals_(new OriginalEntries) {
+WriteTransaction::WriteTransaction(const tracked_objects::Location& location,
+                                   WriterTag writer, Directory* directory)
+    : BaseTransaction(location, "Write", writer, directory),
+      originals_(new OriginalEntries) {
 }
 
-WriteTransaction::WriteTransaction(const ScopedDirLookup& scoped_dir,
+WriteTransaction::WriteTransaction(const tracked_objects::Location& location,
                                    WriterTag writer,
-                                   const tracked_objects::Location& location)
-  : BaseTransaction(scoped_dir.operator -> (), "Write", location, writer),
-    originals_(new OriginalEntries) {
+                                   const ScopedDirLookup& scoped_dir)
+    : BaseTransaction(location, "Write", writer, scoped_dir.operator->()),
+      originals_(new OriginalEntries) {
 }
 
 void WriteTransaction::SaveOriginal(EntryKernel* entry) {
diff --git a/chrome/browser/sync/syncable/syncable.h b/chrome/browser/sync/syncable/syncable.h
index f58cf1c..1f8914b 100644
--- a/chrome/browser/sync/syncable/syncable.h
+++ b/chrome/browser/sync/syncable/syncable.h
@@ -1132,10 +1132,10 @@ class BaseTransaction {
   virtual ~BaseTransaction();
 
  protected:
-  BaseTransaction(Directory* directory,
+  BaseTransaction(const tracked_objects::Location& from_here,
                   const char* name,
-                  const tracked_objects::Location& from_here,
-                  WriterTag writer);
+                  WriterTag writer,
+                  Directory* directory);
 
   void UnlockAndLog(OriginalEntries* entries);
   virtual bool NotifyTransactionChangingAndEnding(
@@ -1143,12 +1143,12 @@ class BaseTransaction {
       ModelTypeBitSet* models_with_changes);
   virtual void NotifyTransactionComplete(ModelTypeBitSet models_with_changes);
 
+  const tracked_objects::Location from_here_;
+  const char* const name_;
+  WriterTag writer_;
   Directory* const directory_;
   Directory::Kernel* const dirkernel_;  // for brevity
-  const char* const name_;
   base::TimeTicks time_acquired_;
-  const tracked_objects::Location from_here_;
-  WriterTag writer_;
 
  private:
   void Lock();
@@ -1159,10 +1159,10 @@ class BaseTransaction {
 // Locks db in constructor, unlocks in destructor.
 class ReadTransaction : public BaseTransaction {
  public:
-  ReadTransaction(Directory* directory,
-                  const tracked_objects::Location& from_here);
-  ReadTransaction(const ScopedDirLookup& scoped_dir,
-                  const tracked_objects::Location& from_here);
+  ReadTransaction(const tracked_objects::Location& from_here,
+                  Directory* directory);
+  ReadTransaction(const tracked_objects::Location& from_here,
+                  const ScopedDirLookup& scoped_dir);
 
   virtual ~ReadTransaction();
 
@@ -1177,10 +1177,11 @@ class ReadTransaction : public BaseTransaction {
 class WriteTransaction : public BaseTransaction {
   friend class MutableEntry;
  public:
-  WriteTransaction(Directory* directory, WriterTag writer,
-                  const tracked_objects::Location& from_here);
-  WriteTransaction(const ScopedDirLookup& directory, WriterTag writer,
-                   const tracked_objects::Location& from_here);
+  WriteTransaction(const tracked_objects::Location& from_here,
+                   WriterTag writer, Directory* directory);
+  WriteTransaction(const tracked_objects::Location& from_here,
+                   WriterTag writer, const ScopedDirLookup& directory);
+
   virtual ~WriteTransaction();
 
   void SaveOriginal(EntryKernel* entry);
diff --git a/chrome/browser/sync/syncable/syncable_mock.cc b/chrome/browser/sync/syncable/syncable_mock.cc
index 5617f48..da5e891 100644
--- a/chrome/browser/sync/syncable/syncable_mock.cc
+++ b/chrome/browser/sync/syncable/syncable_mock.cc
@@ -13,6 +13,6 @@ MockDirectory::MockDirectory() {
 MockDirectory::~MockDirectory() {}
 
 MockSyncableWriteTransaction::MockSyncableWriteTransaction(
-    Directory *directory)
-    : WriteTransaction(directory, syncable::UNITTEST, FROM_HERE) {
+    const tracked_objects::Location& from_here, Directory *directory)
+    : WriteTransaction(from_here, syncable::UNITTEST, directory) {
 }
diff --git a/chrome/browser/sync/syncable/syncable_mock.h b/chrome/browser/sync/syncable/syncable_mock.h
index c20a79b..51692a7 100644
--- a/chrome/browser/sync/syncable/syncable_mock.h
+++ b/chrome/browser/sync/syncable/syncable_mock.h
@@ -34,7 +34,8 @@ class MockDirectory : public Directory {
 
 class MockSyncableWriteTransaction : public syncable::WriteTransaction {
  public:
-  explicit MockSyncableWriteTransaction(Directory *directory);
+  MockSyncableWriteTransaction(
+      const tracked_objects::Location& from_here, Directory *directory);
 };
 
 
diff --git a/chrome/browser/sync/syncable/syncable_unittest.cc b/chrome/browser/sync/syncable/syncable_unittest.cc
index ba801c4..a4b5e43 100644
--- a/chrome/browser/sync/syncable/syncable_unittest.cc
+++ b/chrome/browser/sync/syncable/syncable_unittest.cc
@@ -114,7 +114,7 @@ TEST_F(SyncableGeneralTest, General) {
 
   int64 root_metahandle;
   {
-    ReadTransaction rtrans(&dir, FROM_HERE);
+    ReadTransaction rtrans(FROM_HERE, &dir);
     Entry e(&rtrans, GET_BY_ID, rtrans.root_id());
     ASSERT_TRUE(e.good());
     root_metahandle = e.Get(META_HANDLE);
@@ -125,7 +125,7 @@ TEST_F(SyncableGeneralTest, General) {
   std::string name = "Jeff";
   // Test simple read operations on an empty DB.
   {
-    ReadTransaction rtrans(&dir, FROM_HERE);
+    ReadTransaction rtrans(FROM_HERE, &dir);
     Entry e(&rtrans, GET_BY_ID, id);
     ASSERT_FALSE(e.good());  // Hasn't been written yet.
 
@@ -139,7 +139,7 @@ TEST_F(SyncableGeneralTest, General) {
 
   // Test creating a new meta entry.
   {
-    WriteTransaction wtrans(&dir, UNITTEST, FROM_HERE);
+    WriteTransaction wtrans(FROM_HERE, UNITTEST, &dir);
     MutableEntry me(&wtrans, CREATE, wtrans.root_id(), name);
     ASSERT_TRUE(me.good());
     me.Put(ID, id);
@@ -150,7 +150,7 @@ TEST_F(SyncableGeneralTest, General) {
   // Test GetChildHandles* after something is now in the DB.
   // Also check that GET_BY_ID works.
   {
-    ReadTransaction rtrans(&dir, FROM_HERE);
+    ReadTransaction rtrans(FROM_HERE, &dir);
     Entry e(&rtrans, GET_BY_ID, id);
     ASSERT_TRUE(e.good());
 
@@ -175,7 +175,7 @@ TEST_F(SyncableGeneralTest, General) {
   // Test writing data to an entity. Also check that GET_BY_HANDLE works.
   static const char s[] = "Hello World.";
   {
-    WriteTransaction trans(&dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, &dir);
     MutableEntry e(&trans, GET_BY_HANDLE, written_metahandle);
     ASSERT_TRUE(e.good());
     PutDataAsBookmarkFavicon(&trans, &e, s, sizeof(s));
@@ -183,7 +183,7 @@ TEST_F(SyncableGeneralTest, General) {
 
   // Test reading back the contents that we just wrote.
   {
-    WriteTransaction trans(&dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, &dir);
     MutableEntry e(&trans, GET_BY_HANDLE, written_metahandle);
     ASSERT_TRUE(e.good());
     ExpectDataFromBookmarkFaviconEquals(&trans, &e, s, sizeof(s));
@@ -191,13 +191,13 @@ TEST_F(SyncableGeneralTest, General) {
 
   // Verify it exists in the folder.
   {
-    ReadTransaction rtrans(&dir, FROM_HERE);
+    ReadTransaction rtrans(FROM_HERE, &dir);
     EXPECT_EQ(1, CountEntriesWithName(&rtrans, rtrans.root_id(), name));
   }
 
   // Now delete it.
   {
-    WriteTransaction trans(&dir, UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, &dir);
     MutableEntry e(&trans, GET_BY_HANDLE, written_metahandle);
     e.Put(IS_DEL, true);
 
@@ -219,7 +219,7 @@ TEST_F(SyncableGeneralTest, ClientIndexRebuildsProperly) {
     Directory dir;
     dir.Open(db_path_, "IndexTest", &delegate_);
     {
-      WriteTransaction wtrans(&dir, UNITTEST, FROM_HERE);
+      WriteTransaction wtrans(FROM_HERE, UNITTEST, &dir);
       MutableEntry me(&wtrans, CREATE, wtrans.root_id(), name);
       ASSERT_TRUE(me.good());
       me.Put(ID, id);
@@ -235,7 +235,7 @@ TEST_F(SyncableGeneralTest, ClientIndexRebuildsProperly) {
     Directory dir;
     dir.Open(db_path_, "IndexTest", &delegate_);
 
-    ReadTransaction trans(&dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, &dir);
     Entry me(&trans, GET_BY_CLIENT_TAG, tag);
     ASSERT_TRUE(me.good());
     EXPECT_EQ(me.Get(ID), id);
@@ -255,7 +255,7 @@ TEST_F(SyncableGeneralTest, ClientIndexRebuildsDeletedProperly) {
     Directory dir;
     dir.Open(db_path_, "IndexTest", &delegate_);
     {
-      WriteTransaction wtrans(&dir, UNITTEST, FROM_HERE);
+      WriteTransaction wtrans(FROM_HERE, UNITTEST, &dir);
       MutableEntry me(&wtrans, CREATE, wtrans.root_id(), "deleted");
       ASSERT_TRUE(me.good());
       me.Put(ID, id);
@@ -273,7 +273,7 @@ TEST_F(SyncableGeneralTest, ClientIndexRebuildsDeletedProperly) {
     Directory dir;
     dir.Open(db_path_, "IndexTest", &delegate_);
 
-    ReadTransaction trans(&dir, FROM_HERE);
+    ReadTransaction trans(FROM_HERE, &dir);
     Entry me(&trans, GET_BY_CLIENT_TAG, tag);
     ASSERT_TRUE(me.good());
     EXPECT_EQ(me.Get(ID), id);
@@ -289,7 +289,7 @@ TEST_F(SyncableGeneralTest, ToValue) {
 
   const Id id = TestIdFactory::FromNumber(99);
   {
-    ReadTransaction rtrans(&dir, FROM_HERE);
+    ReadTransaction rtrans(FROM_HERE, &dir);
     Entry e(&rtrans, GET_BY_ID, id);
     EXPECT_FALSE(e.good());  // Hasn't been written yet.
 
@@ -300,7 +300,7 @@ TEST_F(SyncableGeneralTest, ToValue) {
 
   // Test creating a new meta entry.
   {
-    WriteTransaction wtrans(&dir, UNITTEST, FROM_HERE);
+    WriteTransaction wtrans(FROM_HERE, UNITTEST, &dir);
     MutableEntry me(&wtrans, CREATE, wtrans.root_id(), "new");
     ASSERT_TRUE(me.good());
     me.Put(ID, id);
@@ -388,7 +388,7 @@ class SyncableDirectoryTest : public testing::Test {
                                             bool before_reload) {
     SCOPED_TRACE(testing::Message("Before reload: ") << before_reload);
     {
-      ReadTransaction trans(dir_.get(), FROM_HERE);
+      ReadTransaction trans(FROM_HERE, dir_.get());
       MetahandleSet all_set;
       dir_->GetAllMetaHandles(&trans, &all_set);
       EXPECT_EQ(3U, all_set.size());
@@ -423,7 +423,7 @@ class SyncableDirectoryTest : public testing::Test {
     CreateEntry(entryname, TestIdFactory::FromNumber(id));
   }
   void CreateEntry(const std::string& entryname, Id id) {
-    WriteTransaction wtrans(dir_.get(), UNITTEST, FROM_HERE);
+    WriteTransaction wtrans(FROM_HERE, UNITTEST, dir_.get());
     MutableEntry me(&wtrans, CREATE, wtrans.root_id(), entryname);
     ASSERT_TRUE(me.good());
     me.Put(ID, id);
@@ -444,7 +444,7 @@ TEST_F(SyncableDirectoryTest, TakeSnapshotGetsMetahandlesToPurge) {
   MetahandleSet expected_purges;
   MetahandleSet all_handles;
   {
-    WriteTransaction trans(dir_.get(), UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir_.get());
     for (int i = 0; i < metas_to_create; i++) {
       MutableEntry e(&trans, CREATE, trans.root_id(), "foo");
       e.Put(IS_UNSYNCED, true);
@@ -486,7 +486,7 @@ TEST_F(SyncableDirectoryTest, TakeSnapshotGetsAllDirtyHandlesTest) {
   const int metahandles_to_create = 100;
   std::vector<int64> expected_dirty_metahandles;
   {
-    WriteTransaction trans(dir_.get(), UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir_.get());
     for (int i = 0; i < metahandles_to_create; i++) {
       MutableEntry e(&trans, CREATE, trans.root_id(), "foo");
       expected_dirty_metahandles.push_back(e.Get(META_HANDLE));
@@ -509,7 +509,7 @@ TEST_F(SyncableDirectoryTest, TakeSnapshotGetsAllDirtyHandlesTest) {
   }
   // Put a new value with existing transactions as well as adding new ones.
   {
-    WriteTransaction trans(dir_.get(), UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir_.get());
     std::vector<int64> new_dirty_metahandles;
     for (std::vector<int64>::const_iterator i =
         expected_dirty_metahandles.begin();
@@ -560,7 +560,7 @@ TEST_F(SyncableDirectoryTest, TestPurgeEntriesWithTypeIn) {
   TestIdFactory id_factory;
   // Create some items for each type.
   {
-    WriteTransaction trans(dir_.get(), UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir_.get());
     MutableEntry item1(&trans, CREATE, trans.root_id(), "Item");
     ASSERT_TRUE(item1.good());
     item1.Put(SPECIFICS, bookmark_specs);
@@ -600,7 +600,7 @@ TEST_F(SyncableDirectoryTest, TestPurgeEntriesWithTypeIn) {
 
   dir_->SaveChanges();
   {
-    ReadTransaction trans(dir_.get(), FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir_.get());
     MetahandleSet all_set;
     dir_->GetAllMetaHandles(&trans, &all_set);
     ASSERT_EQ(7U, all_set.size());
@@ -622,7 +622,7 @@ TEST_F(SyncableDirectoryTest, TakeSnapshotGetsOnlyDirtyHandlesTest) {
   const unsigned int number_changed = 100u;
   std::vector<int64> expected_dirty_metahandles;
   {
-    WriteTransaction trans(dir_.get(), UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir_.get());
     for (int i = 0; i < metahandles_to_create; i++) {
       MutableEntry e(&trans, CREATE, trans.root_id(), "foo");
       expected_dirty_metahandles.push_back(e.Get(META_HANDLE));
@@ -632,7 +632,7 @@ TEST_F(SyncableDirectoryTest, TakeSnapshotGetsOnlyDirtyHandlesTest) {
   dir_->SaveChanges();
   // Put a new value with existing transactions as well as adding new ones.
   {
-    WriteTransaction trans(dir_.get(), UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir_.get());
     std::vector<int64> new_dirty_metahandles;
     for (std::vector<int64>::const_iterator i =
         expected_dirty_metahandles.begin();
@@ -653,7 +653,7 @@ TEST_F(SyncableDirectoryTest, TakeSnapshotGetsOnlyDirtyHandlesTest) {
   dir_->SaveChanges();
   // Don't make any changes whatsoever and ensure nothing comes back.
   {
-    WriteTransaction trans(dir_.get(), UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir_.get());
     for (std::vector<int64>::const_iterator i =
         expected_dirty_metahandles.begin();
         i != expected_dirty_metahandles.end(); ++i) {
@@ -672,7 +672,7 @@ TEST_F(SyncableDirectoryTest, TakeSnapshotGetsOnlyDirtyHandlesTest) {
     dir_->VacuumAfterSaveChanges(snapshot);
   }
   {
-    WriteTransaction trans(dir_.get(), UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir_.get());
     bool should_change = false;
     for (std::vector<int64>::const_iterator i =
         expected_dirty_metahandles.begin();
@@ -709,21 +709,21 @@ const Id SyncableDirectoryTest::kId(TestIdFactory::FromNumber(-99));
 
 namespace {
 TEST_F(SyncableDirectoryTest, TestBasicLookupNonExistantID) {
-  ReadTransaction rtrans(dir_.get(), FROM_HERE);
+  ReadTransaction rtrans(FROM_HERE, dir_.get());
   Entry e(&rtrans, GET_BY_ID, kId);
   ASSERT_FALSE(e.good());
 }
 
 TEST_F(SyncableDirectoryTest, TestBasicLookupValidID) {
   CreateEntry("rtc");
-  ReadTransaction rtrans(dir_.get(), FROM_HERE);
+  ReadTransaction rtrans(FROM_HERE, dir_.get());
   Entry e(&rtrans, GET_BY_ID, kId);
   ASSERT_TRUE(e.good());
 }
 
 TEST_F(SyncableDirectoryTest, TestDelete) {
   std::string name = "peanut butter jelly time";
-  WriteTransaction trans(dir_.get(), UNITTEST, FROM_HERE);
+  WriteTransaction trans(FROM_HERE, UNITTEST, dir_.get());
   MutableEntry e1(&trans, CREATE, trans.root_id(), name);
   ASSERT_TRUE(e1.good());
   ASSERT_TRUE(e1.Put(IS_DEL, true));
@@ -747,7 +747,7 @@ TEST_F(SyncableDirectoryTest, TestGetUnsynced) {
   Directory::UnsyncedMetaHandles handles;
   int64 handle1, handle2;
   {
-    WriteTransaction trans(dir_.get(), UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir_.get());
 
     dir_->GetUnsyncedMetaHandles(&trans, &handles);
     ASSERT_TRUE(0 == handles.size());
@@ -767,7 +767,7 @@ TEST_F(SyncableDirectoryTest, TestGetUnsynced) {
   }
   dir_->SaveChanges();
   {
-    WriteTransaction trans(dir_.get(), UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir_.get());
 
     dir_->GetUnsyncedMetaHandles(&trans, &handles);
     ASSERT_TRUE(0 == handles.size());
@@ -778,7 +778,7 @@ TEST_F(SyncableDirectoryTest, TestGetUnsynced) {
   }
   dir_->SaveChanges();
   {
-    WriteTransaction trans(dir_.get(), UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir_.get());
     dir_->GetUnsyncedMetaHandles(&trans, &handles);
     ASSERT_TRUE(1 == handles.size());
     ASSERT_TRUE(handle1 == handles[0]);
@@ -789,7 +789,7 @@ TEST_F(SyncableDirectoryTest, TestGetUnsynced) {
   }
   dir_->SaveChanges();
   {
-    WriteTransaction trans(dir_.get(), UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir_.get());
     dir_->GetUnsyncedMetaHandles(&trans, &handles);
     ASSERT_TRUE(2 == handles.size());
     if (handle1 == handles[0]) {
@@ -807,7 +807,7 @@ TEST_F(SyncableDirectoryTest, TestGetUnsynced) {
   }
   dir_->SaveChanges();
   {
-    WriteTransaction trans(dir_.get(), UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir_.get());
     dir_->GetUnsyncedMetaHandles(&trans, &handles);
     ASSERT_TRUE(1 == handles.size());
     ASSERT_TRUE(handle2 == handles[0]);
@@ -818,7 +818,7 @@ TEST_F(SyncableDirectoryTest, TestGetUnappliedUpdates) {
   Directory::UnappliedUpdateMetaHandles handles;
   int64 handle1, handle2;
   {
-    WriteTransaction trans(dir_.get(), UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir_.get());
 
     dir_->GetUnappliedUpdateMetaHandles(&trans, &handles);
     ASSERT_TRUE(0 == handles.size());
@@ -840,7 +840,7 @@ TEST_F(SyncableDirectoryTest, TestGetUnappliedUpdates) {
   }
   dir_->SaveChanges();
   {
-    WriteTransaction trans(dir_.get(), UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir_.get());
 
     dir_->GetUnappliedUpdateMetaHandles(&trans, &handles);
     ASSERT_TRUE(0 == handles.size());
@@ -851,7 +851,7 @@ TEST_F(SyncableDirectoryTest, TestGetUnappliedUpdates) {
   }
   dir_->SaveChanges();
   {
-    WriteTransaction trans(dir_.get(), UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir_.get());
     dir_->GetUnappliedUpdateMetaHandles(&trans, &handles);
     ASSERT_TRUE(1 == handles.size());
     ASSERT_TRUE(handle1 == handles[0]);
@@ -862,7 +862,7 @@ TEST_F(SyncableDirectoryTest, TestGetUnappliedUpdates) {
   }
   dir_->SaveChanges();
   {
-    WriteTransaction trans(dir_.get(), UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir_.get());
     dir_->GetUnappliedUpdateMetaHandles(&trans, &handles);
     ASSERT_TRUE(2 == handles.size());
     if (handle1 == handles[0]) {
@@ -878,7 +878,7 @@ TEST_F(SyncableDirectoryTest, TestGetUnappliedUpdates) {
   }
   dir_->SaveChanges();
   {
-    WriteTransaction trans(dir_.get(), UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir_.get());
     dir_->GetUnappliedUpdateMetaHandles(&trans, &handles);
     ASSERT_TRUE(1 == handles.size());
     ASSERT_TRUE(handle2 == handles[0]);
@@ -891,7 +891,7 @@ TEST_F(SyncableDirectoryTest, DeleteBug_531383) {
   TestIdFactory id_factory;
   int64 grandchild_handle, twin_handle;
   {
-    WriteTransaction wtrans(dir_.get(), UNITTEST, FROM_HERE);
+    WriteTransaction wtrans(FROM_HERE, UNITTEST, dir_.get());
     MutableEntry parent(&wtrans, CREATE, id_factory.root(), "Bob");
     ASSERT_TRUE(parent.good());
     parent.Put(IS_DIR, true);
@@ -917,7 +917,7 @@ TEST_F(SyncableDirectoryTest, DeleteBug_531383) {
   }
   dir_->SaveChanges();
   {
-    WriteTransaction wtrans(dir_.get(), UNITTEST, FROM_HERE);
+    WriteTransaction wtrans(FROM_HERE, UNITTEST, dir_.get());
     MutableEntry grandchild(&wtrans, GET_BY_HANDLE, grandchild_handle);
     grandchild.Put(IS_DEL, true);  // Used to CHECK fail here.
   }
@@ -929,7 +929,7 @@ static inline bool IsLegalNewParent(const Entry& a, const Entry& b) {
 
 TEST_F(SyncableDirectoryTest, TestIsLegalNewParent) {
   TestIdFactory id_factory;
-  WriteTransaction wtrans(dir_.get(), UNITTEST, FROM_HERE);
+  WriteTransaction wtrans(FROM_HERE, UNITTEST, dir_.get());
   Entry root(&wtrans, GET_BY_ID, id_factory.root());
   ASSERT_TRUE(root.good());
   MutableEntry parent(&wtrans, CREATE, root.Get(ID), "Bob");
@@ -988,7 +988,7 @@ TEST_F(SyncableDirectoryTest, TestEntryIsInFolder) {
   std::string entry_name = "entry";
 
   {
-    WriteTransaction trans(dir_.get(), UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir_.get());
     MutableEntry folder(&trans, CREATE, trans.root_id(), "folder");
     ASSERT_TRUE(folder.good());
     EXPECT_TRUE(folder.Put(IS_DIR, true));
@@ -1004,7 +1004,7 @@ TEST_F(SyncableDirectoryTest, TestEntryIsInFolder) {
 
   // Make sure we can find the entry in the folder.
   {
-    ReadTransaction trans(dir_.get(), FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir_.get());
     EXPECT_EQ(0, CountEntriesWithName(&trans, trans.root_id(), entry_name));
     EXPECT_EQ(1, CountEntriesWithName(&trans, folder_id, entry_name));
 
@@ -1019,7 +1019,7 @@ TEST_F(SyncableDirectoryTest, TestEntryIsInFolder) {
 TEST_F(SyncableDirectoryTest, TestParentIdIndexUpdate) {
   std::string child_name = "child";
 
-  WriteTransaction wt(dir_.get(), UNITTEST, FROM_HERE);
+  WriteTransaction wt(FROM_HERE, UNITTEST, dir_.get());
   MutableEntry parent_folder(&wt, CREATE, wt.root_id(), "folder1");
   parent_folder.Put(IS_UNSYNCED, true);
   EXPECT_TRUE(parent_folder.Put(IS_DIR, true));
@@ -1048,7 +1048,7 @@ TEST_F(SyncableDirectoryTest, TestNoReindexDeletedItems) {
   std::string folder_name = "folder";
   std::string new_name = "new_name";
 
-  WriteTransaction trans(dir_.get(), UNITTEST, FROM_HERE);
+  WriteTransaction trans(FROM_HERE, UNITTEST, dir_.get());
   MutableEntry folder(&trans, CREATE, trans.root_id(), folder_name);
   ASSERT_TRUE(folder.good());
   ASSERT_TRUE(folder.Put(IS_DIR, true));
@@ -1066,7 +1066,7 @@ TEST_F(SyncableDirectoryTest, TestNoReindexDeletedItems) {
 }
 
 TEST_F(SyncableDirectoryTest, TestCaseChangeRename) {
-  WriteTransaction trans(dir_.get(), UNITTEST, FROM_HERE);
+  WriteTransaction trans(FROM_HERE, UNITTEST, dir_.get());
   MutableEntry folder(&trans, CREATE, trans.root_id(), "CaseChange");
   ASSERT_TRUE(folder.good());
   EXPECT_TRUE(folder.Put(PARENT_ID, trans.root_id()));
@@ -1079,7 +1079,7 @@ TEST_F(SyncableDirectoryTest, TestShareInfo) {
   dir_->set_store_birthday("Jan 31st");
   dir_->SetNotificationState("notification_state");
   {
-    ReadTransaction trans(dir_.get(), FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir_.get());
     EXPECT_TRUE(dir_->initial_sync_ended_for_type(AUTOFILL));
     EXPECT_FALSE(dir_->initial_sync_ended_for_type(BOOKMARKS));
     EXPECT_EQ("Jan 31st", dir_->store_birthday());
@@ -1090,7 +1090,7 @@ TEST_F(SyncableDirectoryTest, TestShareInfo) {
   dir_->SetNotificationState("notification_state2");
   dir_->SaveChanges();
   {
-    ReadTransaction trans(dir_.get(), FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir_.get());
     EXPECT_TRUE(dir_->initial_sync_ended_for_type(AUTOFILL));
     EXPECT_FALSE(dir_->initial_sync_ended_for_type(BOOKMARKS));
     EXPECT_EQ("April 10th", dir_->store_birthday());
@@ -1101,7 +1101,7 @@ TEST_F(SyncableDirectoryTest, TestShareInfo) {
   // Restore the directory from disk.  Make sure that nothing's changed.
   SaveAndReloadDir();
   {
-    ReadTransaction trans(dir_.get(), FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir_.get());
     EXPECT_TRUE(dir_->initial_sync_ended_for_type(AUTOFILL));
     EXPECT_FALSE(dir_->initial_sync_ended_for_type(BOOKMARKS));
     EXPECT_EQ("April 10th", dir_->store_birthday());
@@ -1118,7 +1118,7 @@ TEST_F(SyncableDirectoryTest, TestSimpleFieldsPreservedDuringSaveChanges) {
   std::string create_name =  "Create";
 
   {
-    WriteTransaction trans(dir_.get(), UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir_.get());
     MutableEntry create(&trans, CREATE, trans.root_id(), create_name);
     MutableEntry update(&trans, CREATE_NEW_UPDATE_ITEM, update_id);
     create.Put(IS_UNSYNCED, true);
@@ -1139,7 +1139,7 @@ TEST_F(SyncableDirectoryTest, TestSimpleFieldsPreservedDuringSaveChanges) {
   ASSERT_TRUE(dir_->good());
 
   {
-    ReadTransaction trans(dir_.get(), FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir_.get());
     Entry create(&trans, GET_BY_ID, create_id);
     EXPECT_EQ(1, CountEntriesWithName(&trans, trans.root_id(), create_name));
     Entry update(&trans, GET_BY_ID, update_id);
@@ -1193,7 +1193,7 @@ TEST_F(SyncableDirectoryTest, TestSaveChangesFailure) {
   int64 handle1 = 0;
   // Set up an item using a regular, saveable directory.
   {
-    WriteTransaction trans(dir_.get(), UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir_.get());
 
     MutableEntry e1(&trans, CREATE, trans.root_id(), "aguilera");
     ASSERT_TRUE(e1.good());
@@ -1210,7 +1210,7 @@ TEST_F(SyncableDirectoryTest, TestSaveChangesFailure) {
   // Make sure the item is no longer dirty after saving,
   // and make a modification.
   {
-    WriteTransaction trans(dir_.get(), UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir_.get());
 
     MutableEntry aguilera(&trans, GET_BY_HANDLE, handle1);
     ASSERT_TRUE(aguilera.good());
@@ -1230,7 +1230,7 @@ TEST_F(SyncableDirectoryTest, TestSaveChangesFailure) {
   ASSERT_TRUE(dir_->good());
   int64 handle2 = 0;
   {
-    WriteTransaction trans(dir_.get(), UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir_.get());
 
     MutableEntry aguilera(&trans, GET_BY_HANDLE, handle1);
     ASSERT_TRUE(aguilera.good());
@@ -1259,7 +1259,7 @@ TEST_F(SyncableDirectoryTest, TestSaveChangesFailure) {
 
   // Make sure things were rolled back and the world is as it was before call.
   {
-     ReadTransaction trans(dir_.get(), FROM_HERE);
+     ReadTransaction trans(FROM_HERE, dir_.get());
      Entry e1(&trans, GET_BY_HANDLE, handle1);
      ASSERT_TRUE(e1.good());
      EntryKernel aguilera = e1.GetKernelCopy();
@@ -1276,7 +1276,7 @@ TEST_F(SyncableDirectoryTest, TestSaveChangesFailureWithPurge) {
   int64 handle1 = 0;
   // Set up an item using a regular, saveable directory.
   {
-    WriteTransaction trans(dir_.get(), UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir_.get());
 
     MutableEntry e1(&trans, CREATE, trans.root_id(), "aguilera");
     ASSERT_TRUE(e1.good());
@@ -1327,7 +1327,7 @@ TEST_F(SyncableDirectoryTest, GetModelType) {
     sync_pb::EntitySpecifics specifics;
     AddDefaultExtensionValue(datatype, &specifics);
 
-    WriteTransaction trans(dir_.get(), UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir_.get());
 
     MutableEntry folder(&trans, CREATE, trans.root_id(), "Folder");
     ASSERT_TRUE(folder.good());
@@ -1506,7 +1506,7 @@ class ThreadBugDelegate : public base::PlatformThread::Delegate {
           directory_manager_->Open(dirname, &delegate_);
           ScopedDirLookup dir(directory_manager_, dirname);
           CHECK(dir.good());
-          WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+          WriteTransaction trans(FROM_HERE, UNITTEST, dir);
           MutableEntry me(&trans, CREATE, trans.root_id(), "Jeff");
           step_->metahandle = me.Get(META_HANDLE);
           me.Put(IS_UNSYNCED, true);
@@ -1516,7 +1516,7 @@ class ThreadBugDelegate : public base::PlatformThread::Delegate {
         {
           ScopedDirLookup dir(directory_manager_, dirname);
           CHECK(dir.good());
-          ReadTransaction trans(dir, FROM_HERE);
+          ReadTransaction trans(FROM_HERE, dir);
           Entry e(&trans, GET_BY_HANDLE, step_->metahandle);
           CHECK(e.good());  // Failed due to ThreadBug1
         }
@@ -1580,7 +1580,7 @@ class DirectoryKernelStalenessBugDelegate : public ThreadBugDelegate {
           directory_manager_->Open(dirname, &delegate_);
           ScopedDirLookup dir(directory_manager_, dirname);
           CHECK(dir.good());
-          WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+          WriteTransaction trans(FROM_HERE, UNITTEST, dir);
           MutableEntry me(&trans, CREATE, trans.root_id(), "Jeff");
           me.Put(BASE_VERSION, 1);
           me.Put(ID, jeff_id);
@@ -1611,7 +1611,7 @@ class DirectoryKernelStalenessBugDelegate : public ThreadBugDelegate {
         {
           ScopedDirLookup dir(directory_manager_, dirname);
           CHECK(dir.good());
-          ReadTransaction trans(dir, FROM_HERE);
+          ReadTransaction trans(FROM_HERE, dir);
           Entry e(&trans, GET_BY_ID, jeff_id);
           ExpectDataFromBookmarkFaviconEquals(&trans, &e, test_bytes,
                                                 sizeof(test_bytes));
@@ -1671,14 +1671,14 @@ class StressTransactionsDelegate : public base::PlatformThread::Delegate {
     for (int i = 0; i < 20; ++i) {
       const int rand_action = rand() % 10;
       if (rand_action < 4 && !path_name.empty()) {
-        ReadTransaction trans(dir, FROM_HERE);
+        ReadTransaction trans(FROM_HERE, dir);
         CHECK(1 == CountEntriesWithName(&trans, trans.root_id(), path_name));
         base::PlatformThread::Sleep(rand() % 10);
       } else {
         std::string unique_name =
             base::StringPrintf("%d.%d", thread_number_, entry_count++);
         path_name.assign(unique_name.begin(), unique_name.end());
-        WriteTransaction trans(dir, UNITTEST, FROM_HERE);
+        WriteTransaction trans(FROM_HERE, UNITTEST, dir);
         MutableEntry e(&trans, CREATE, trans.root_id(), path_name);
         CHECK(e.good());
         base::PlatformThread::Sleep(rand() % 20);
@@ -1736,7 +1736,7 @@ class SyncableClientTagTest : public SyncableDirectoryTest {
 
   // Attempt to create an entry with a default tag.
   bool CreateWithTag(const char* tag, Id id, bool deleted) {
-    WriteTransaction wtrans(dir_.get(), UNITTEST, FROM_HERE);
+    WriteTransaction wtrans(FROM_HERE, UNITTEST, dir_.get());
     MutableEntry me(&wtrans, CREATE, wtrans.root_id(), test_name_);
     CHECK(me.good());
     me.Put(ID, id);
@@ -1752,7 +1752,7 @@ class SyncableClientTagTest : public SyncableDirectoryTest {
   // Verify an entry exists with the default tag.
   void VerifyTag(Id id, bool deleted) {
     // Should still be present and valid in the client tag index.
-    ReadTransaction trans(dir_.get(), FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir_.get());
     Entry me(&trans, GET_BY_CLIENT_TAG, test_tag_);
     CHECK(me.good());
     EXPECT_EQ(me.Get(ID), id);
@@ -1769,13 +1769,13 @@ TEST_F(SyncableClientTagTest, TestClientTagClear) {
   Id server_id = factory_.NewServerId();
   EXPECT_TRUE(CreateWithDefaultTag(server_id, false));
   {
-    WriteTransaction trans(dir_.get(), UNITTEST, FROM_HERE);
+    WriteTransaction trans(FROM_HERE, UNITTEST, dir_.get());
     MutableEntry me(&trans, GET_BY_CLIENT_TAG, test_tag_);
     EXPECT_TRUE(me.good());
     me.Put(UNIQUE_CLIENT_TAG, "");
   }
   {
-    ReadTransaction trans(dir_.get(), FROM_HERE);
+    ReadTransaction trans(FROM_HERE, dir_.get());
     Entry by_tag(&trans, GET_BY_CLIENT_TAG, test_tag_);
     EXPECT_FALSE(by_tag.good());