Clean up the strings for sync code:

- Use FilePath for real file paths.
- Use std::string for PathString on Windows as well

TODO in a separate CL:
- Get rid of PathString typedef completely and directly use std::string everywhere.
- Use wchar_t in syncapi.h/.cc and get rid of sync_char16.

TEST=Existing tests are sufficient since this CL does a lot of code refactoring.
BUG=26342

Review URL: http://codereview.chromium.org/340055

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@30970 0039d316-1c4b-4281-b951-d872f2087c98

16 files changed, 46 insertions, 115 deletions

diff --git a/chrome/browser/sync/engine/apply_updates_command_unittest.cc b/chrome/browser/sync/engine/apply_updates_command_unittest.cc
index afa0969..aff2c63 100644
--- a/chrome/browser/sync/engine/apply_updates_command_unittest.cc
+++ b/chrome/browser/sync/engine/apply_updates_command_unittest.cc
@@ -9,7 +9,6 @@
 #include "chrome/browser/sync/syncable/directory_manager.h"
 #include "chrome/browser/sync/syncable/syncable.h"
 #include "chrome/browser/sync/syncable/syncable_id.h"
-#include "chrome/browser/sync/util/character_set_converters.h"
 #include "chrome/test/sync/engine/test_directory_setter_upper.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
@@ -46,12 +45,10 @@ class ApplyUpdatesCommandTest : public testing::Test {
     MutableEntry entry(&trans, syncable::CREATE_NEW_UPDATE_ITEM,
         Id::CreateFromServerId(item_id));
     ASSERT_TRUE(entry.good());
-    PathString name;
-    AppendUTF8ToPathString(item_id, &name);
     entry.Put(syncable::SERVER_VERSION, next_revision_++);
     entry.Put(syncable::IS_UNAPPLIED_UPDATE, true);
-    entry.Put(syncable::SERVER_NAME, name);
-    entry.Put(syncable::SERVER_NON_UNIQUE_NAME, name);
+    entry.Put(syncable::SERVER_NAME, item_id);
+    entry.Put(syncable::SERVER_NON_UNIQUE_NAME, item_id);
     entry.Put(syncable::SERVER_PARENT_ID, Id::CreateFromServerId(parent_id));
     entry.Put(syncable::SERVER_IS_DIR, true);
   }
diff --git a/chrome/browser/sync/engine/auth_watcher.cc b/chrome/browser/sync/engine/auth_watcher.cc
index c722a8d..9d81d28 100644
--- a/chrome/browser/sync/engine/auth_watcher.cc
+++ b/chrome/browser/sync/engine/auth_watcher.cc
@@ -13,7 +13,6 @@
 #include "chrome/browser/sync/notifier/listener/talk_mediator.h"
 #include "chrome/browser/sync/syncable/directory_manager.h"
 #include "chrome/browser/sync/syncable/syncable.h"
-#include "chrome/browser/sync/util/character_set_converters.h"
 #include "chrome/browser/sync/util/event_sys-inl.h"
 #include "chrome/browser/sync/util/user_settings.h"
 
@@ -122,8 +121,7 @@ void AuthWatcher::DoAuthenticateWithToken(const std::string& gaia_email,
     case Authenticator::SUCCESS:
       {
         status_ = GAIA_AUTHENTICATED;
-        PathString share_name;
-        CHECK(AppendUTF8ToPathString(email.data(), email.size(), &share_name));
+        const PathString& share_name = email;
         user_settings_->SwitchUser(email);
 
         // Set the authentication token for notifications
@@ -165,8 +163,7 @@ bool AuthWatcher::AuthenticateLocally(string email) {
     gaia_->SetUsername(email);
     status_ = LOCALLY_AUTHENTICATED;
     user_settings_->SwitchUser(email);
-    PathString share_name;
-    CHECK(AppendUTF8ToPathString(email.data(), email.size(), &share_name));
+    const PathString& share_name = email;
     LoadDirectoryListAndOpen(share_name);
     NotifyAuthSucceeded(email);
     return true;
diff --git a/chrome/browser/sync/engine/auth_watcher_unittest.cc b/chrome/browser/sync/engine/auth_watcher_unittest.cc
index ede4023..c2561630 100644
--- a/chrome/browser/sync/engine/auth_watcher_unittest.cc
+++ b/chrome/browser/sync/engine/auth_watcher_unittest.cc
@@ -86,7 +86,7 @@ class AuthWatcherTest : public testing::Test {
     allstatus_.reset(new AllStatus());
     user_settings_.reset(new UserSettings());
     ASSERT_TRUE(temp_dir_.CreateUniqueTempDir());
-    PathString user_settings_path = temp_dir_.path().value() + kUserSettingsDB;
+    FilePath user_settings_path = temp_dir_.path().Append(kUserSettingsDB);
     user_settings_->Init(user_settings_path);
     gaia_auth_ = new GaiaAuthMockForAuthWatcher();
     talk_mediator_.reset(new TalkMediatorImpl());
diff --git a/chrome/browser/sync/engine/build_commit_command.cc b/chrome/browser/sync/engine/build_commit_command.cc
index 5058bba..07ae99a 100644
--- a/chrome/browser/sync/engine/build_commit_command.cc
+++ b/chrome/browser/sync/engine/build_commit_command.cc
@@ -14,7 +14,6 @@
 #include "chrome/browser/sync/engine/syncproto.h"
 #include "chrome/browser/sync/syncable/syncable.h"
 #include "chrome/browser/sync/syncable/syncable_changes_version.h"
-#include "chrome/browser/sync/util/character_set_converters.h"
 #include "chrome/browser/sync/util/sync_types.h"
 
 using std::set;
@@ -46,7 +45,7 @@ void BuildCommitCommand::AddExtensionsActivityToMessage(
 
 void BuildCommitCommand::ExecuteImpl(SyncerSession* session) {
   ClientToServerMessage message;
-  message.set_share(ToUTF8(session->account_name()).get_string());
+  message.set_share(session->account_name());
   message.set_message_contents(ClientToServerMessage::COMMIT);
 
   CommitMessage* commit_message = message.mutable_commit();
@@ -69,15 +68,14 @@ void BuildCommitCommand::ExecuteImpl(SyncerSession* session) {
 
     Name name = meta_entry.GetName();
     CHECK(!name.value().empty());  // Make sure this isn't an update.
-    sync_entry->set_name(ToUTF8(name.value()).get_string());
+    sync_entry->set_name(name.value());
     // Set the non_unique_name if we have one.  If we do, the server ignores
     // the |name| value (using |non_unique_name| instead), and will return
     // in the CommitResponse a unique name if one is generated.  Even though
     // we could get away with only sending |name|, we send both because it
     // may aid in logging.
     if (name.value() != name.non_unique_value()) {
-      sync_entry->set_non_unique_name(
-        ToUTF8(name.non_unique_value()).get_string());
+      sync_entry->set_non_unique_name(name.non_unique_value());
     }
     // Deleted items with negative parent ids can be a problem so we set the
     // parent to 0. (TODO(sync): Still true in protocol?).
@@ -126,7 +124,7 @@ void BuildCommitCommand::ExecuteImpl(SyncerSession* session) {
         ++iter) {
       sync_pb::ExtendedAttributes_ExtendedAttribute *extended_attribute =
           mutable_extended_attributes->add_extendedattribute();
-      extended_attribute->set_key(ToUTF8(iter->key()).get_string());
+      extended_attribute->set_key(iter->key());
       SyncerProtoUtil::CopyBlobIntoProtoBytes(iter->value(),
           extended_attribute->mutable_value());
     }
@@ -143,7 +141,7 @@ void BuildCommitCommand::ExecuteImpl(SyncerSession* session) {
       sync_entry->set_insert_after_item_id(prev_string);
 
       if (!meta_entry.Get(syncable::IS_DIR)) {
-        string bookmark_url = ToUTF8(meta_entry.Get(syncable::BOOKMARK_URL));
+        string bookmark_url = meta_entry.Get(syncable::BOOKMARK_URL);
         bookmark->set_bookmark_url(bookmark_url);
         SyncerProtoUtil::CopyBlobIntoProtoBytes(
             meta_entry.Get(syncable::BOOKMARK_FAVICON),
diff --git a/chrome/browser/sync/engine/download_updates_command.cc b/chrome/browser/sync/engine/download_updates_command.cc
index 889567e..1883e31 100644
--- a/chrome/browser/sync/engine/download_updates_command.cc
+++ b/chrome/browser/sync/engine/download_updates_command.cc
@@ -10,7 +10,6 @@
 #include "chrome/browser/sync/engine/syncer_proto_util.h"
 #include "chrome/browser/sync/engine/syncproto.h"
 #include "chrome/browser/sync/syncable/directory_manager.h"
-#include "chrome/browser/sync/util/character_set_converters.h"
 #include "chrome/browser/sync/util/sync_types.h"
 
 using syncable::ScopedDirLookup;
@@ -26,8 +25,7 @@ void DownloadUpdatesCommand::ExecuteImpl(SyncerSession* session) {
   ClientToServerMessage client_to_server_message;
   ClientToServerResponse update_response;
 
-  client_to_server_message.set_share(
-      static_cast<const string&>(ToUTF8(session->account_name())));
+  client_to_server_message.set_share(session->account_name());
   client_to_server_message.set_message_contents(
       ClientToServerMessage::GET_UPDATES);
   GetUpdatesMessage* get_updates =
diff --git a/chrome/browser/sync/engine/net/server_connection_manager.cc b/chrome/browser/sync/engine/net/server_connection_manager.cc
index c8165a9..38d140f 100644
--- a/chrome/browser/sync/engine/net/server_connection_manager.cc
+++ b/chrome/browser/sync/engine/net/server_connection_manager.cc
@@ -18,7 +18,6 @@
 #include "chrome/browser/sync/engine/syncproto.h"
 #include "chrome/browser/sync/protocol/sync.pb.h"
 #include "chrome/browser/sync/syncable/directory_manager.h"
-#include "chrome/browser/sync/util/character_set_converters.h"
 #include "chrome/browser/sync/util/event_sys-inl.h"
 
 namespace browser_sync {
@@ -355,7 +354,7 @@ bool FillMessageWithShareDetails(sync_pb::ClientToServerMessage* csm,
   string birthday = dir->store_birthday();
   if (!birthday.empty())
     csm->set_store_birthday(birthday);
-  csm->set_share(ToUTF8(share).get_string());
+  csm->set_share(share);
   return true;
 }
 
diff --git a/chrome/browser/sync/engine/net/url_translator.cc b/chrome/browser/sync/engine/net/url_translator.cc
index 8a1c0a3..6dc2754 100644
--- a/chrome/browser/sync/engine/net/url_translator.cc
+++ b/chrome/browser/sync/engine/net/url_translator.cc
@@ -10,7 +10,6 @@
 #include "base/basictypes.h"
 #include "base/logging.h"
 #include "base/port.h"
-#include "chrome/browser/sync/util/character_set_converters.h"
 #include "net/base/escape.h"
 
 using std::string;
diff --git a/chrome/browser/sync/engine/process_commit_response_command.cc b/chrome/browser/sync/engine/process_commit_response_command.cc
index 72fd0e6..de993fb 100644
--- a/chrome/browser/sync/engine/process_commit_response_command.cc
+++ b/chrome/browser/sync/engine/process_commit_response_command.cc
@@ -15,7 +15,6 @@
 #include "chrome/browser/sync/engine/syncproto.h"
 #include "chrome/browser/sync/syncable/directory_manager.h"
 #include "chrome/browser/sync/syncable/syncable.h"
-#include "chrome/browser/sync/util/character_set_converters.h"
 
 using syncable::ScopedDirLookup;
 using syncable::WriteTransaction;
diff --git a/chrome/browser/sync/engine/process_updates_command.cc b/chrome/browser/sync/engine/process_updates_command.cc
index 31d267d..fefa234 100644
--- a/chrome/browser/sync/engine/process_updates_command.cc
+++ b/chrome/browser/sync/engine/process_updates_command.cc
@@ -14,7 +14,6 @@
 #include "chrome/browser/sync/engine/syncproto.h"
 #include "chrome/browser/sync/syncable/directory_manager.h"
 #include "chrome/browser/sync/syncable/syncable.h"
-#include "chrome/browser/sync/util/character_set_converters.h"
 
 using std::vector;
 
diff --git a/chrome/browser/sync/engine/syncapi.cc b/chrome/browser/sync/engine/syncapi.cc
index 7d953d0..7cf18bc 100644
--- a/chrome/browser/sync/engine/syncapi.cc
+++ b/chrome/browser/sync/engine/syncapi.cc
@@ -133,8 +133,8 @@ class AddressWatchTask : public Task {
 namespace sync_api {
 class ModelSafeWorkerBridge;
 
-static const PSTR_CHAR kBookmarkSyncUserSettingsDatabase[] =
-    PSTR("BookmarkSyncSettings.sqlite3");
+static const FilePath::CharType kBookmarkSyncUserSettingsDatabase[] =
+    FILE_PATH_LITERAL("BookmarkSyncSettings.sqlite3");
 static const PSTR_CHAR kDefaultNameForNewNodes[] = PSTR(" ");
 
 // The list of names which are reserved for use by the server.
@@ -171,29 +171,11 @@ static bool EndsWithSpace(const string16& string) {
   return !string.empty() && *string.rbegin() == ' ';
 }
 
-static inline void String16ToPathString(const sync_char16 *in,
-                                        PathString *out) {
-  string16 in_str(in);
-#if defined(OS_WIN)
-  out->assign(in_str);
-#else
-  UTF16ToUTF8(in_str.c_str(), in_str.length(), out);
-#endif
-}
-
-static inline void PathStringToString16(const PathString& in, string16* out) {
-#if defined(OS_WIN)
-  out->assign(in);
-#else
-  UTF8ToUTF16(in.c_str(), in.length(), out);
-#endif
-}
-
 // When taking a name from the syncapi, append a space if it matches the
 // pattern of a server-illegal name followed by zero or more spaces.
 static void SyncAPINameToServerName(const sync_char16 *sync_api_name,
                                     PathString* out) {
-  String16ToPathString(sync_api_name, out);
+  *out = UTF16ToUTF8(sync_api_name);
   string16 sync_api_name_str(sync_api_name);
   if (IsNameServerIllegalAfterTrimming(sync_api_name_str))
     out->append(PSTR(" "));
@@ -204,8 +186,7 @@ static void SyncAPINameToServerName(const sync_char16 *sync_api_name,
 // space.
 static void ServerNameToSyncAPIName(const PathString& server_name,
                                     string16*out) {
-  string16 server_name_str;
-  PathStringToString16(server_name, &server_name_str);
+  string16 server_name_str(UTF8ToUTF16(server_name));
   if (IsNameServerIllegalAfterTrimming(server_name_str) &&
       EndsWithSpace(server_name_str))
     out->assign(server_name_str, 0, server_name_str.size() - 1);
@@ -272,7 +253,7 @@ const sync_char16* BaseNode::GetTitle() const {
 
 const sync_char16* BaseNode::GetURL() const {
   // Store the string in data_ so that the returned pointer is valid.
-  PathStringToString16(GetEntry()->Get(syncable::BOOKMARK_URL), &data_->url);
+  data_->url = UTF8ToUTF16(GetEntry()->Get(syncable::BOOKMARK_URL));
   return data_->url.c_str();
 }
 
@@ -357,8 +338,7 @@ void WriteNode::SetTitle(const sync_char16* title) {
 }
 
 void WriteNode::SetURL(const sync_char16* url) {
-  PathString url_string;
-  String16ToPathString(url, &url_string);
+  PathString url_string(UTF16ToUTF8(url));
   if (url_string == entry_->Get(syncable::BOOKMARK_URL))
     return;  // Skip redundant changes.
 
@@ -543,8 +523,7 @@ const BaseTransaction* ReadNode::GetTransaction() const {
 
 bool ReadNode::InitByTagLookup(const sync_char16* tag) {
   DCHECK(!entry_) << "Init called twice";
-  PathString tag_string;
-  String16ToPathString(tag, &tag_string);
+  PathString tag_string(UTF16ToUTF8(tag));
   if (tag_string.empty())
     return false;
   syncable::BaseTransaction* trans = transaction_->GetWrappedTrans();
@@ -702,7 +681,7 @@ class SyncManager::SyncInternal {
 
   ~SyncInternal() { }
 
-  bool Init(const PathString& database_location,
+  bool Init(const FilePath& database_location,
             const std::string& sync_server_and_path,
             int port,
             const char* gaia_service_id,
@@ -941,7 +920,7 @@ SyncManager::SyncManager() {
   data_ = new SyncInternal(this);
 }
 
-bool SyncManager::Init(const sync_char16* database_location,
+bool SyncManager::Init(const FilePath& database_location,
                        const char* sync_server_and_path,
                        int sync_server_port,
                        const char* gaia_service_id,
@@ -952,13 +931,10 @@ bool SyncManager::Init(const sync_char16* database_location,
                        ModelSafeWorkerInterface* model_safe_worker,
                        bool attempt_last_user_authentication,
                        const char* user_agent) {
-  DCHECK(database_location);
   DCHECK(post_factory);
 
-  PathString db_path;
-  String16ToPathString(database_location, &db_path);
   string server_string(sync_server_and_path);
-  return data_->Init(db_path,
+  return data_->Init(database_location,
                      server_string,
                      sync_server_port,
                      gaia_service_id,
@@ -982,13 +958,12 @@ const char* SyncManager::GetAuthenticatedUsername() {
 }
 
 const char* SyncManager::SyncInternal::GetAuthenticatedUsername() {
-  cached_auth_watcher_email_ = browser_sync::ToUTF8(
-      username_for_share()).get_string();
+  cached_auth_watcher_email_ = username_for_share();
   return cached_auth_watcher_email_.c_str();
 }
 
 bool SyncManager::SyncInternal::Init(
-    const PathString& database_location,
+    const FilePath& database_location,
     const std::string& sync_server_and_path,
     int port,
     const char* gaia_service_id,
@@ -1001,8 +976,8 @@ bool SyncManager::SyncInternal::Init(
 
   // Set up UserSettings, creating the db if necessary. We need this to
   // instantiate a URLFactory to give to the Syncer.
-  PathString settings_db_file = AppendSlash(database_location) +
-                                kBookmarkSyncUserSettingsDatabase;
+  FilePath settings_db_file =
+      database_location.Append(FilePath(kBookmarkSyncUserSettingsDatabase));
   user_settings_.reset(new UserSettings());
   if (!user_settings_->Init(settings_db_file))
     return false;
@@ -1103,8 +1078,7 @@ void SyncManager::SyncInternal::MarkAndNotifyInitializationComplete() {
 
 void SyncManager::SyncInternal::Authenticate(const std::string& username,
                                              const std::string& password) {
-  DCHECK(username_for_share().empty() ||
-        (username == browser_sync::ToUTF8(username_for_share()).get_string()))
+  DCHECK(username_for_share().empty() || username == username_for_share())
         << "Username change from valid username detected";
   if (allstatus()->status().authenticated)
     return;
@@ -1127,13 +1101,7 @@ void SyncManager::SyncInternal::AuthenticateForLastKnownUser() {
     return;
   }
 
-  browser_sync::ToPathString s(username);
-  if (s.good()) {
-    share_.authenticated_name = s.get_string16();
-  } else {
-    RaiseAuthNeededEvent();
-    return;
-  }
+  share_.authenticated_name = username;
 
   // We optimize by opening the directory before the "fresh" authentication
   // attempt completes so that we can immediately begin processing changes.
@@ -1449,16 +1417,12 @@ void SyncManager::SyncInternal::HandleAuthWatcherEvent(
       // We now know the supplied username and password were valid. If this
       // wasn't the first sync, authenticated_name should already be assigned.
       if (username_for_share().empty()) {
-        browser_sync::ToPathString s(event.user_email);
-        if (s.good())
-          share_.authenticated_name = s.get_string16();
+        share_.authenticated_name = event.user_email;
       }
 
-      DCHECK(LowerCaseEqualsASCII(browser_sync::ToUTF8(
-          username_for_share()).get_string(),
+      DCHECK(LowerCaseEqualsASCII(username_for_share(),
           StringToLowerASCII(event.user_email).c_str()))
-          << "username_for_share= "
-          << browser_sync::ToUTF8(username_for_share())
+          << "username_for_share= " << username_for_share()
           << ", event.user_email= " << event.user_email;
 
       if (observer_)
@@ -1536,7 +1500,7 @@ void SyncManager::SetupForTestMode(const sync_char16* test_username) {
 
 void SyncManager::SyncInternal::SetupForTestMode(
     const sync_char16* test_username) {
-  String16ToPathString(test_username, &share_.authenticated_name);
+  share_.authenticated_name = UTF16ToUTF8(test_username);
 
   if (!dir_manager()->Open(username_for_share()))
     DCHECK(false) << "Could not open directory when running in test mode";
diff --git a/chrome/browser/sync/engine/syncapi.h b/chrome/browser/sync/engine/syncapi.h
index 474a7a5..f85b25b 100644
--- a/chrome/browser/sync/engine/syncapi.h
+++ b/chrome/browser/sync/engine/syncapi.h
@@ -39,6 +39,7 @@
 #define CHROME_BROWSER_SYNC_ENGINE_SYNCAPI_H_
 
 #include "base/basictypes.h"
+#include "base/file_path.h"
 #include "build/build_config.h"
 
 #if defined(OS_WIN)
@@ -523,7 +524,7 @@ class SYNC_EXPORT SyncManager {
   // |model_safe_worker| ownership is given to the SyncManager.
   // |user_agent| is a 7-bit ASCII string suitable for use as the User-Agent
   // HTTP header. Used internally when collecting stats to classify clients.
-  bool Init(const sync_char16* database_location,
+  bool Init(const FilePath& database_location,
             const char* sync_server_and_path,
             int sync_server_port,
             const char* gaia_service_id,
diff --git a/chrome/browser/sync/engine/syncer.cc b/chrome/browser/sync/engine/syncer.cc
index ee56bb9..ee92258 100644
--- a/chrome/browser/sync/engine/syncer.cc
+++ b/chrome/browser/sync/engine/syncer.cc
@@ -26,7 +26,6 @@
 #include "chrome/browser/sync/syncable/directory_manager.h"
 #include "chrome/browser/sync/syncable/syncable-inl.h"
 #include "chrome/browser/sync/syncable/syncable.h"
-#include "chrome/browser/sync/util/character_set_converters.h"
 
 using sync_pb::ClientCommand;
 using syncable::Blob;
diff --git a/chrome/browser/sync/engine/syncer_proto_util.cc b/chrome/browser/sync/engine/syncer_proto_util.cc
index 4896c59..7eb0227 100644
--- a/chrome/browser/sync/engine/syncer_proto_util.cc
+++ b/chrome/browser/sync/engine/syncer_proto_util.cc
@@ -11,7 +11,6 @@
 #include "chrome/browser/sync/syncable/directory_manager.h"
 #include "chrome/browser/sync/syncable/syncable-inl.h"
 #include "chrome/browser/sync/syncable/syncable.h"
-#include "chrome/browser/sync/util/character_set_converters.h"
 
 using std::string;
 using std::stringstream;
@@ -246,14 +245,9 @@ void SyncerProtoUtil::CopyBlobIntoProtoBytes(const syncable::Blob& blob,
 // static
 syncable::SyncName SyncerProtoUtil::NameFromSyncEntity(
     const SyncEntity& entry) {
-  SyncName result(PSTR(""));
-
-  AppendUTF8ToPathString(entry.name(), &result.value());
+  SyncName result(entry.name());
   if (entry.has_non_unique_name()) {
-    AppendUTF8ToPathString(entry.non_unique_name(),
-                           &result.non_unique_value());
-  } else {
-    result.non_unique_value() = result.value();
+    result.set_non_unique_value(entry.non_unique_name());
   }
   return result;
 }
@@ -261,14 +255,9 @@ syncable::SyncName SyncerProtoUtil::NameFromSyncEntity(
 // static
 syncable::SyncName SyncerProtoUtil::NameFromCommitEntryResponse(
     const CommitResponse_EntryResponse& entry) {
-  SyncName result(PSTR(""));
-
-  AppendUTF8ToPathString(entry.name(), &result.value());
+  SyncName result(entry.name());
   if (entry.has_non_unique_name()) {
-    AppendUTF8ToPathString(entry.non_unique_name(),
-                           &result.non_unique_value());
-  } else {
-    result.non_unique_value() = result.value();
+    result.set_non_unique_value(entry.non_unique_name());
   }
   return result;
 }
diff --git a/chrome/browser/sync/engine/syncer_unittest.cc b/chrome/browser/sync/engine/syncer_unittest.cc
index 288ed42..47a67bc 100644
--- a/chrome/browser/sync/engine/syncer_unittest.cc
+++ b/chrome/browser/sync/engine/syncer_unittest.cc
@@ -27,8 +27,6 @@
 #include "chrome/browser/sync/protocol/sync.pb.h"
 #include "chrome/browser/sync/syncable/directory_manager.h"
 #include "chrome/browser/sync/syncable/syncable.h"
-#include "chrome/browser/sync/util/character_set_converters.h"
-#include "chrome/browser/sync/util/compat_file.h"
 #include "chrome/browser/sync/util/event_sys-inl.h"
 #include "chrome/test/sync/engine/mock_server_connection.h"
 #include "chrome/test/sync/engine/test_directory_setter_upper.h"
@@ -1392,14 +1390,13 @@ TEST_F(SyncerTest, CommitTimeRenameI18N) {
   // Verify it was correctly renamed.
   {
     ReadTransaction trans(dir, __FILE__, __LINE__);
-    PathString expectedFolder;
-    AppendUTF8ToPathString(i18nString, &expectedFolder);
-    AppendUTF8ToPathString("Folder", &expectedFolder);
+    PathString expectedFolder(i18nString);
+    expectedFolder.append("Folder");
     Entry entry_folder(&trans, GET_BY_PATH, expectedFolder);
     ASSERT_TRUE(entry_folder.good());
     PathString expected = expectedFolder + PathString(kPathSeparator);
-    AppendUTF8ToPathString(i18nString, &expected);
-    AppendUTF8ToPathString("new_entry", &expected);
+    expected.append(i18nString);
+    expected.append("new_entry");
 
     Entry entry_new(&trans, GET_BY_PATH, expected);
     ASSERT_TRUE(entry_new.good());
diff --git a/chrome/browser/sync/engine/syncer_util.cc b/chrome/browser/sync/engine/syncer_util.cc
index 4074cd6..6828297 100644
--- a/chrome/browser/sync/engine/syncer_util.cc
+++ b/chrome/browser/sync/engine/syncer_util.cc
@@ -15,7 +15,6 @@
 #include "chrome/browser/sync/syncable/directory_manager.h"
 #include "chrome/browser/sync/syncable/syncable.h"
 #include "chrome/browser/sync/syncable/syncable_changes_version.h"
-#include "chrome/browser/sync/util/character_set_converters.h"
 #include "chrome/browser/sync/util/path_helpers.h"
 #include "chrome/browser/sync/util/sync_types.h"
 
@@ -329,15 +328,13 @@ void SyncerUtil::UpdateServerFieldsFromUpdate(
   local_entry->Put(SERVER_IS_BOOKMARK_OBJECT, server_entry.has_bookmarkdata());
   local_entry->Put(SERVER_IS_DIR, server_entry.IsFolder());
   if (server_entry.has_singleton_tag()) {
-    PathString tag;
-    AppendUTF8ToPathString(server_entry.singleton_tag(), &tag);
+    const PathString& tag = server_entry.singleton_tag();
     local_entry->Put(SINGLETON_TAG, tag);
   }
   if (server_entry.has_bookmarkdata() && !server_entry.deleted()) {
     const SyncEntity::BookmarkData& bookmark = server_entry.bookmarkdata();
     if (bookmark.has_bookmark_url()) {
-      PathString url;
-      AppendUTF8ToPathString(bookmark.bookmark_url(), &url);
+      const PathString& url = bookmark.bookmark_url();
       local_entry->Put(SERVER_BOOKMARK_URL, url);
     }
     if (bookmark.has_bookmark_favicon()) {
@@ -371,9 +368,8 @@ void SyncerUtil::ApplyExtendedAttributes(
     const sync_pb::ExtendedAttributes & extended_attributes =
       server_entry.extended_attributes();
     for (int i = 0; i < extended_attributes.extendedattribute_size(); i++) {
-      PathString pathstring_key;
-      AppendUTF8ToPathString(
-          extended_attributes.extendedattribute(i).key(), &pathstring_key);
+      const PathString& pathstring_key =
+          extended_attributes.extendedattribute(i).key();
       ExtendedAttributeKey key(local_entry->Get(META_HANDLE), pathstring_key);
       MutableExtendedAttribute local_attribute(local_entry->write_transaction(),
           CREATE, key);
diff --git a/chrome/browser/sync/engine/verify_updates_command.cc b/chrome/browser/sync/engine/verify_updates_command.cc
index 7a23477..83d0257 100644
--- a/chrome/browser/sync/engine/verify_updates_command.cc
+++ b/chrome/browser/sync/engine/verify_updates_command.cc
@@ -12,7 +12,6 @@
 #include "chrome/browser/sync/engine/syncproto.h"
 #include "chrome/browser/sync/syncable/directory_manager.h"
 #include "chrome/browser/sync/syncable/syncable.h"
-#include "chrome/browser/sync/util/character_set_converters.h"
 #include "chrome/browser/sync/util/sync_types.h"
 
 namespace browser_sync {