[Android] Make BookmarkModelObserver more convenient.

chrome/browser/android/bookmarks/bookmarks_bridge.h

 // Copyright 2013 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_ANDROID_BOOKMARKS_BOOKMARKS_BRIDGE_H_
 #define CHROME_BROWSER_ANDROID_BOOKMARKS_BOOKMARKS_BRIDGE_H_
 
 #include <jni.h>
 
 #include "base/android/jni_android.h"
@@ skipping 11 matching lines @@
 // bookmark page. This fetches the bookmarks, title, urls, folder
 // hierarchy.
 class BookmarksBridge : public BaseBookmarkModelObserver,
                         public PartnerBookmarksShim::Observer {
  public:
   BookmarksBridge(JNIEnv* env, jobject obj, jobject j_profile);
   void Destroy(JNIEnv*, jobject);
 
   static bool RegisterBookmarksBridge(JNIEnv* env);
 
+  bool IsDoingExtensiveChanges(JNIEnv* env, jobject obj);
+
   base::android::ScopedJavaLocalRef<jobject> GetBookmarkByID(
       JNIEnv* env,
       jobject obj,
       jlong id,
       jint type);
 
   void GetPermanentNodeIDs(JNIEnv* env,
                            jobject obj,
                            jobject j_result_obj);
 
@@ skipping 127 matching lines @@
   ChromeBookmarkClient* client_;   // weak
 
   // Information about the Partner bookmarks (must check for IsLoaded()).
   // This is owned by profile.
   PartnerBookmarksShim* partner_bookmarks_shim_;
 
   DISALLOW_COPY_AND_ASSIGN(BookmarksBridge);
 };
 
 #endif  // CHROME_BROWSER_ANDROID_BOOKMARKS_BOOKMARKS_BRIDGE_H_