Remove sync OnTransaction{Start,End} notification

chrome/browser/sync/js/js_mutation_event_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_MUTATION_EVENT_OBSERVER_H_
 #define CHROME_BROWSER_SYNC_JS_JS_MUTATION_EVENT_OBSERVER_H_
 #pragma once
 
 #include <string>
 
@@ skipping 31 matching lines @@
   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;
 
   // syncable::TransactionObserver implementation.
-  virtual void OnTransactionStart(
-      const tracked_objects::Location& location,
-      const syncable::WriterTag& writer) OVERRIDE;
   virtual void OnTransactionWrite(
       const syncable::ImmutableWriteTransactionInfo& write_transaction_info,
       const syncable::ModelTypeBitSet& models_with_changes) OVERRIDE;
-  virtual void OnTransactionEnd(
-      const tracked_objects::Location& location,
-      const syncable::WriterTag& writer) OVERRIDE;
 
  private:
   base::NonThreadSafe non_thread_safe_;
   base::WeakPtrFactory<JsMutationEventObserver> weak_ptr_factory_;
   WeakHandle<JsEventHandler> event_handler_;
 
   void HandleJsEvent(
     const tracked_objects::Location& from_here,
     const std::string& name, const JsEventDetails& details);
 
   DISALLOW_COPY_AND_ASSIGN(JsMutationEventObserver);
 };
 
 }  // namespace browser_sync
 
 #endif  // CHROME_BROWSER_SYNC_JS_JS_MUTATION_EVENT_OBSERVER_H_