content: Cleanup class/struct forward declarations

content/renderer/media/media_stream_audio_processor_options.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 CONTENT_RENDERER_MEDIA_MEDIA_STREAM_AUDIO_PROCESSOR_OPTIONS_H_
 #define CONTENT_RENDERER_MEDIA_MEDIA_STREAM_AUDIO_PROCESSOR_OPTIONS_H_
 
 #include <string>
 
 #include "base/files/file.h"
 #include "base/macros.h"
 #include "base/threading/thread_checker.h"
 #include "content/common/content_export.h"
 #include "content/public/common/media_stream_request.h"
 #include "third_party/WebKit/public/platform/WebMediaConstraints.h"
 #include "third_party/webrtc/api/mediastreaminterface.h"
 #include "third_party/webrtc/media/base/mediachannel.h"
 #include "third_party/webrtc/modules/audio_processing/include/audio_processing.h"
 
 namespace webrtc {
 
 class EchoCancellation;
 class TypingDetection;
 
 }
 
 namespace content {
 
-class RTCMediaConstraints;
-
 using webrtc::AudioProcessing;
 
 // A helper class to parse audio constraints from a blink::WebMediaConstraints
 // object.
 class CONTENT_EXPORT MediaAudioConstraints {
  public:
   // Constraint keys used by audio processing.
   static const char kEchoCancellation[];
   static const char kGoogEchoCancellation[];
   static const char kGoogExperimentalEchoCancellation[];
@@ skipping 126 matching lines @@
 
 // Returns the array geometry from the media constraints if existing and
 // otherwise that provided by the input device.
 CONTENT_EXPORT std::vector<webrtc::Point> GetArrayGeometryPreferringConstraints(
     const MediaAudioConstraints& audio_constraints,
     const MediaStreamDevice::AudioDeviceParameters& input_params);
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_MEDIA_MEDIA_STREAM_AUDIO_PROCESSOR_OPTIONS_H_