Cleanup: Remove unneeded forward declarations from chrome/browser/extensions.

chrome/browser/extensions/extension_tts_api_controller.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_EXTENSIONS_EXTENSION_TTS_API_CONTROLLER_H_
 #define CHROME_BROWSER_EXTENSIONS_EXTENSION_TTS_API_CONTROLLER_H_
 
 #include <queue>
 #include <set>
 #include <string>
 
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/singleton.h"
 #include "googleurl/src/gurl.h"
 
 class Extension;
 class ExtensionTtsPlatformImpl;
 class Profile;
 
 namespace base {
-class DictionaryValue;
 class ListValue;
 class Value;
 }
 
 // Events sent back from the TTS engine indicating the progress.
 enum TtsEventType {
   TTS_EVENT_START,
   TTS_EVENT_END,
   TTS_EVENT_WORD,
   TTS_EVENT_SENTENCE,
@@ skipping 217 matching lines @@
   std::queue<Utterance*> utterance_queue_;
 
   // A pointer to the platform implementation of text-to-speech, for
   // dependency injection.
   ExtensionTtsPlatformImpl* platform_impl_;
 
   DISALLOW_COPY_AND_ASSIGN(ExtensionTtsController);
 };
 
 #endif  // CHROME_BROWSER_EXTENSIONS_EXTENSION_TTS_API_CONTROLLER_H_