[Sync] Move some code into new class JsMutationEventObserver

chrome/browser/sync/js/js_sync_manager_observer.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_JS_JS_SYNC_MANAGER_OBSERVER_H_
 #define CHROME_BROWSER_SYNC_JS_JS_SYNC_MANAGER_OBSERVER_H_
 #pragma once
 
 #include <string>
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "chrome/browser/sync/internal_api/sync_manager.h"
 #include "chrome/browser/sync/protocol/sync_protocol_error.h"
 #include "chrome/browser/sync/util/weak_handle.h"
 
 namespace tracked_objects {
 class Location;
 }  // namespace tracked_objects
 
 namespace browser_sync {
 
 class JsEventDetails;
 class JsEventHandler;
 
 // Routes SyncManager events to a JsEventHandler.
-class JsSyncManagerObserver
-    : public sync_api::SyncManager::ChangeObserver,
-      public sync_api::SyncManager::Observer {
+class JsSyncManagerObserver : public sync_api::SyncManager::Observer {
  public:
   JsSyncManagerObserver();
   virtual ~JsSyncManagerObserver();
 
   void SetJsEventHandler(const WeakHandle<JsEventHandler>& event_handler);
 
-  // sync_api::SyncManager::ChangeObserver implementation.
-  virtual void OnChangesApplied(
-      syncable::ModelType model_type,
-      int64 write_transaction_id,
-      const sync_api::ImmutableChangeRecordList& changes) OVERRIDE;
-  virtual void OnChangesComplete(syncable::ModelType model_type) OVERRIDE;
-
   // sync_api::SyncManager::Observer implementation.
   virtual void OnSyncCycleCompleted(
       const sessions::SyncSessionSnapshot* snapshot) OVERRIDE;
   virtual void OnAuthError(const GoogleServiceAuthError& auth_error) OVERRIDE;
   virtual void OnUpdatedToken(const std::string& token) OVERRIDE;
   virtual void OnPassphraseRequired(
       sync_api::PassphraseRequiredReason reason) OVERRIDE;
   virtual void OnPassphraseAccepted(
       const std::string& bootstrap_token) OVERRIDE;
   virtual void OnEncryptionComplete(
@@ skipping 11 matching lines @@
                     const std::string& name, const JsEventDetails& details);
 
   WeakHandle<JsEventHandler> event_handler_;
 
   DISALLOW_COPY_AND_ASSIGN(JsSyncManagerObserver);
 };
 
 }  // namespace browser_sync
 
 #endif  // CHROME_BROWSER_SYNC_JS_JS_SYNC_MANAGER_OBSERVER_H_