support video device enumeration from renderer process.

content/browser/renderer_host/media/media_stream_requester.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 CONTENT_BROWSER_RENDERER_HOST_MEDIA_MEDIA_STREAM_REQUESTER_H_
 #define CONTENT_BROWSER_RENDERER_HOST_MEDIA_MEDIA_STREAM_REQUESTER_H_
 
 #include <string>
 
 #include "content/common/content_export.h"
@@ skipping 12 matching lines @@
                                const StreamDeviceInfoArray& video_devices) = 0;
   // Called if GenerateStream failed.
   virtual void StreamGenerationFailed(const std::string& label) = 0;
   // AudioDeviceFailed is called if an already opened audio device encounters
   // an error.
   virtual void AudioDeviceFailed(const std::string& label, int index) = 0;
   // VideoDeviceFailed is called if an already opened video device encounters
   // an error.
   virtual void VideoDeviceFailed(const std::string& label, int index) = 0;
 
+  // Called as a reply of a successful call to EnumerateDevices.
+  virtual void DevicesEnumerated(const std::string& label,
+                                 const StreamDeviceInfoArray& devices) = 0;
+  // Called if EnumerateDevices failed.
+  virtual void DevicesEnumerationFailed(const std::string& label) = 0;
+  // Called as a reply of a successful call to OpenDevice.
+  virtual void DeviceOpened(const std::string& label,
+                            const StreamDeviceInfo& device_info) = 0;
+  // Called if OpenDevice failed.
+  virtual void DeviceOpenFailed(const std::string& label) = 0;
+
  protected:
   virtual ~MediaStreamRequester() {
   }
 };
 
 }  // namespace media_stream
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_MEDIA_MEDIA_STREAM_REQUESTER_H_