Add non-blocking sync code to ProfileSyncService

chrome/browser/sync/glue/sync_backend_host_impl.h

Index: chrome/browser/sync/glue/sync_backend_host_impl.h
diff --git a/chrome/browser/sync/glue/sync_backend_host_impl.h b/chrome/browser/sync/glue/sync_backend_host_impl.h
index d4568a245cb69658e28da410d80da9014f0cec37..3a35a16b2ce124bb22a876b9e2ed033a3df7adb1 100644
--- a/chrome/browser/sync/glue/sync_backend_host_impl.h
+++ b/chrome/browser/sync/glue/sync_backend_host_impl.h
@@ -112,6 +112,7 @@ class SyncBackendHostImpl
       ChangeProcessor* change_processor) OVERRIDE;
   virtual void DeactivateDataType(syncer::ModelType type) OVERRIDE;
   virtual syncer::UserShare* GetUserShare() const OVERRIDE;
+  virtual syncer::SyncCoreProxy GetSyncCoreProxy() OVERRIDE;
   virtual Status GetDetailedStatus() OVERRIDE;
   virtual syncer::sessions::SyncSessionSnapshot
       GetLastSessionSnapshot() const OVERRIDE;
@@ -162,7 +163,8 @@ class SyncBackendHostImpl
   virtual void HandleInitializationSuccessOnFrontendLoop(
     const syncer::WeakHandle<syncer::JsBackend> js_backend,
     const syncer::WeakHandle<syncer::DataTypeDebugInfoListener>
-        debug_info_listener);
+        debug_info_listener,
+    syncer::SyncCoreProxy sync_core_proxy);
 
   // Downloading of control types failed and will be retried. Invokes the
   // frontend's sync configure retry method.
@@ -287,6 +289,9 @@ class SyncBackendHostImpl
   // sync loop.
   scoped_refptr<SyncBackendHostCore> core_;
 
+  // A handle referencing the main interface for non-blocking sync types.
+  scoped_ptr<syncer::SyncCoreProxy> sync_core_proxy_;
+
   bool initialized_;
 
   const base::WeakPtr<sync_driver::SyncPrefs> sync_prefs_;