[Sync] Refactor non-frontend DTC to handle new API properly.

chrome/browser/sync/api/syncable_service_mock.h

 // Copyright (c) 2011 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.
 
 #ifndef CHROME_BROWSER_SYNC_API_SYNCABLE_SERVICE_MOCK_H_
 #define CHROME_BROWSER_SYNC_API_SYNCABLE_SERVICE_MOCK_H_
 #pragma once
 
 #include "base/location.h"
+#include "base/memory/weak_ptr.h"
 #include "chrome/browser/sync/api/syncable_service.h"
 #include "chrome/browser/sync/api/sync_change.h"
 #include "testing/gmock/include/gmock/gmock.h"
 
-class SyncableServiceMock : public SyncableService {
+class SyncableServiceMock : public SyncableService,
+                            public base::SupportsWeakPtr<SyncableServiceMock> {
  public:
   SyncableServiceMock();
   virtual ~SyncableServiceMock();
 
   MOCK_METHOD3(MergeDataAndStartSyncing,
                SyncError(syncable::ModelType,
                          const SyncDataList&,
                          SyncChangeProcessor* sync_processor));
   MOCK_METHOD1(StopSyncing, void(syncable::ModelType));
   MOCK_CONST_METHOD1(GetAllSyncData, SyncDataList(syncable::ModelType type));
   MOCK_METHOD2(ProcessSyncChanges,
                SyncError(const tracked_objects::Location&,
                          const SyncChangeList&));
 };
 
 #endif  // CHROME_BROWSER_SYNC_API_SYNCABLE_SERVICE_MOCK_H_