blink: Cleanup class forward declarations

third_party/WebKit/Source/modules/audio_output_devices/AudioOutputDeviceClient.h

 // Copyright 2015 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 AudioOutputDeviceClient_h
 #define AudioOutputDeviceClient_h
 
 #include "core/frame/LocalFrame.h"
 #include "modules/ModulesExport.h"
 #include "platform/Supplementable.h"
 #include "public/platform/WebSetSinkIdCallbacks.h"
 #include <memory>
 
 namespace blink {
 
 class ExecutionContext;
 class WebString;
-class ScriptState;
 
 class MODULES_EXPORT AudioOutputDeviceClient : public Supplement<LocalFrame> {
  public:
   virtual ~AudioOutputDeviceClient() {}
 
   // Checks that a given sink exists and has permissions to be used from the
   // origin of the current frame.
   virtual void checkIfAudioSinkExistsAndIsAuthorized(
       ExecutionContext*,
       const WebString& sinkId,
       std::unique_ptr<WebSetSinkIdCallbacks>) = 0;
 
   DECLARE_VIRTUAL_TRACE();
 
   // Supplement requirements.
   static AudioOutputDeviceClient* from(ExecutionContext*);
   static const char* supplementName();
 };
 
 MODULES_EXPORT void provideAudioOutputDeviceClientTo(LocalFrame&,
                                                      AudioOutputDeviceClient*);
 
 }  // namespace blink
 
 #endif  // AudioOutputDeviceClient_h