Implement SyncableServices in TemplateURLService. Add related unittests.

chrome/browser/sync/api/sync_change.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_SYNC_CHANGE_H_
 #define CHROME_BROWSER_SYNC_API_SYNC_CHANGE_H_
 #pragma once
 
 #include <string>
 #include <vector>
@@ skipping 27 matching lines @@
   // Deletes: Requires valid tag when going to the syncer. Requires valid
   //          specifics when coming from the syncer.
   // Adds, Updates: Require valid tag and specifics when going to the syncer.
   //                Require only valid specifics when coming from the syncer.
   bool IsValid() const;
 
   // Getters.
   SyncChangeType change_type() const;
   SyncData sync_data() const;
 
+  // Returns a string representation of |change_type|.
+  static std::string ChangeTypeToString(SyncChangeType change_type);
+
  private:
   SyncChangeType change_type_;
 
   // An immutable container for the data of this SyncChange. Whenever
   // SyncChanges are copied, they copy references to this data.
   SyncData sync_data_;
 };
 
 #endif  // CHROME_BROWSER_SYNC_API_SYNC_CHANGE_H_