Hook up Autofill Backend interface to SyncableServices

components/webdata/common/web_database_service.h

Index: components/webdata/common/web_database_service.h
diff --git a/components/webdata/common/web_database_service.h b/components/webdata/common/web_database_service.h
index 1bdfca8504edc317b12d9360a1082f07262fc8f3..f8e7bf673b02cc396cbd56f4ec35dfa67237d2f2 100644
--- a/components/webdata/common/web_database_service.h
+++ b/components/webdata/common/web_database_service.h
@@ -51,6 +51,7 @@ class WEBDATA_EXPORT WebDatabaseService
  public:
   typedef base::Callback<scoped_ptr<WDTypedResult>(WebDatabase*)> ReadTask;
   typedef base::Callback<WebDatabase::State(WebDatabase*)> WriteTask;
+  typedef base::Callback<void(base::WeakPtr<WebDatabase>)> DBCallback;
 
   // Takes the path to the WebDatabase file.
   explicit WebDatabaseService(const base::FilePath& path);
@@ -71,9 +72,10 @@ class WEBDATA_EXPORT WebDatabaseService
   // Unloads database and will not reload.
   virtual void ShutdownDatabase();
 
-  // Gets a ptr to the WebDatabase (owned by WebDatabaseService).
-  // TODO(caitkp): remove this method once SyncServices no longer depend on it.
-  virtual WebDatabase* GetDatabaseOnDB() const;
+  // Asynchronously gets an instance of |WebDatabase|, which can be
+  // used to do work on the DB thread. This method is meant to be called from
+  // the UI thread, but the callback will be called on the DB thread.
+  void GetDatabaseOnDB(const DBCallback& callback);
 
   // Schedule an update/write task on the DB thread.
   virtual void ScheduleDBTask(