Remove cancelMediaDevicesRequest dead code.

content/renderer/media/user_media_client_impl.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 CONTENT_RENDERER_MEDIA_USER_MEDIA_CLIENT_IMPL_H_
 #define CONTENT_RENDERER_MEDIA_USER_MEDIA_CLIENT_IMPL_H_
 
 #include <memory>
 #include <string>
 #include <vector>
@@ skipping 46 matching lines @@
     return media_stream_dispatcher_.get();
   }
 
   // blink::WebUserMediaClient implementation
   void requestUserMedia(
       const blink::WebUserMediaRequest& user_media_request) override;
   void cancelUserMediaRequest(
       const blink::WebUserMediaRequest& user_media_request) override;
   void requestMediaDevices(
       const blink::WebMediaDevicesRequest& media_devices_request) override;
-  void cancelMediaDevicesRequest(
-      const blink::WebMediaDevicesRequest& media_devices_request) override;
   void requestSources(
       const blink::WebMediaStreamTrackSourcesRequest& sources_request) override;
   void setMediaDeviceChangeObserver(
       const blink::WebMediaDeviceChangeObserver& observer) override;
 
   // MediaStreamDispatcherEventHandler implementation.
   void OnStreamGenerated(int request_id,
                          const std::string& label,
                          const StreamDeviceInfoArray& audio_array,
                          const StreamDeviceInfoArray& video_array) override;
@@ skipping 194 matching lines @@
   // Note: This member must be the last to ensure all outstanding weak pointers
   // are invalidated first.
   base::WeakPtrFactory<UserMediaClientImpl> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(UserMediaClientImpl);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_MEDIA_USER_MEDIA_CLIENT_IMPL_H_