chrome: Cleanup class/struct forward declarations

chrome/browser/history/android/android_provider_backend.h

 // Copyright (c) 2012 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_HISTORY_ANDROID_ANDROID_PROVIDER_BACKEND_H_
 #define CHROME_BROWSER_HISTORY_ANDROID_ANDROID_PROVIDER_BACKEND_H_
 
 #include <list>
 #include <memory>
 #include <set>
 
 #include "base/containers/hash_tables.h"
 #include "base/files/file_path.h"
 #include "base/gtest_prod_util.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/supports_user_data.h"
 #include "components/history/core/browser/android/android_cache_database.h"
 #include "components/history/core/browser/android/android_history_types.h"
 #include "components/history/core/browser/android/sql_handler.h"
 
 namespace history {
 
 class AndroidProviderBackend;
-class AndroidURLsSQLHandler;
 class HistoryBackend;
 class HistoryBackendClient;
 class HistoryBackendNotifier;
 class HistoryDatabase;
 class ThumbnailDatabase;
 
 // This class provides the query/insert/update/remove methods to implement
 // android.provider.Browser.BookmarkColumns and
 // android.provider.Browser.SearchColumns API.
 //
@@ skipping 309 matching lines @@
   bool initialized_;
 
   HistoryBackendNotifier* notifier_;
 
   DISALLOW_COPY_AND_ASSIGN(AndroidProviderBackend);
 };
 
 }  // namespace history
 
 #endif  // CHROME_BROWSER_HISTORY_ANDROID_ANDROID_PROVIDER_BACKEND_H_