Sync: Turn on full history sync by default.

chrome/browser/sync/profile_sync_components_factory_impl.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/command_line.h"
 #include "build/build_config.h"
 #include "chrome/browser/bookmarks/bookmark_model_factory.h"
 #include "chrome/browser/extensions/api/storage/settings_frontend.h"
 #include "chrome/browser/extensions/extension_service.h"
 #include "chrome/browser/extensions/extension_system.h"
@@ skipping 128 matching lines @@
   }
 
   // TypedUrl sync is enabled by default.  Register unless explicitly disabled,
   // or if saving history is disabled.
   if (!profile_->GetPrefs()->GetBoolean(prefs::kSavingBrowserHistoryDisabled) &&
       !command_line_->HasSwitch(switches::kDisableSyncTypedUrls)) {
     pss->RegisterDataTypeController(
         new TypedUrlDataTypeController(this, profile_, pss));
   }
 
-  // Unless it is explicitly disabled, history delete directive sync is
-  // enabled whenever full history sync is enabled.
-  if (command_line_->HasSwitch(switches::kHistoryEnableFullHistorySync) &&
-      !command_line_->HasSwitch(
-          switches::kDisableSyncHistoryDeleteDirectives)) {
+  // Delete directive sync is enabled by default.  Register unless full history
+  // sync is disabled.
+  if (!command_line_->HasSwitch(switches::kHistoryDisableFullHistorySync)) {
     pss->RegisterDataTypeController(
         new UIDataTypeController(
             syncer::HISTORY_DELETE_DIRECTIVES, this, profile_, pss));
   }
 
   // Session sync is enabled by default.  Register unless explicitly disabled.
   if (!command_line_->HasSwitch(switches::kDisableSyncTabs)) {
     pss->RegisterDataTypeController(
         new ProxyDataTypeController(syncer::PROXY_TABS));
     pss->RegisterDataTypeController(
@@ skipping 271 matching lines @@
 ProfileSyncComponentsFactory::SyncComponents
     ProfileSyncComponentsFactoryImpl::CreateSessionSyncComponents(
        ProfileSyncService* profile_sync_service,
         DataTypeErrorHandler* error_handler) {
   SessionModelAssociator* model_associator =
       new SessionModelAssociator(profile_sync_service, error_handler);
   SessionChangeProcessor* change_processor =
       new SessionChangeProcessor(error_handler, model_associator);
   return SyncComponents(model_associator, change_processor);
 }