[Sync] Make SESSIONS an implicit type

chrome/browser/sync/profile_sync_components_factory_impl.cc

Index: chrome/browser/sync/profile_sync_components_factory_impl.cc
diff --git a/chrome/browser/sync/profile_sync_components_factory_impl.cc b/chrome/browser/sync/profile_sync_components_factory_impl.cc
index acdefbaa24fc86cbe8ceaecdcadce613d759b717..9c50415a761cdab3270fe087c368a41a720cfec4 100644
--- a/chrome/browser/sync/profile_sync_components_factory_impl.cc
+++ b/chrome/browser/sync/profile_sync_components_factory_impl.cc
@@ -30,6 +30,7 @@
 #include "chrome/browser/sync/glue/extension_data_type_controller.h"
 #include "chrome/browser/sync/glue/extension_setting_data_type_controller.h"
 #include "chrome/browser/sync/glue/generic_change_processor.h"
+#include "chrome/browser/sync/glue/virtual_data_type_controller.h"
 #include "chrome/browser/sync/glue/password_change_processor.h"
 #include "chrome/browser/sync/glue/password_data_type_controller.h"
 #include "chrome/browser/sync/glue/password_model_associator.h"
@@ -71,6 +72,7 @@ using browser_sync::DataTypeManagerObserver;
 using browser_sync::ExtensionDataTypeController;
 using browser_sync::ExtensionSettingDataTypeController;
 using browser_sync::GenericChangeProcessor;
+using browser_sync::VirtualDataTypeController;
 using browser_sync::PasswordChangeProcessor;
 using browser_sync::PasswordDataTypeController;
 using browser_sync::PasswordModelAssociator;
@@ -129,6 +131,8 @@ void ProfileSyncComponentsFactoryImpl::RegisterCommonDataTypes(
   // Session sync is enabled by default.  Register unless explicitly disabled.
   if (!command_line_->HasSwitch(switches::kDisableSyncTabs)) {
     pss->RegisterDataTypeController(
+        new VirtualDataTypeController(syncer::TABS));
+    pss->RegisterDataTypeController(
         new SessionDataTypeController(this, profile_, pss));
   }
 }