Android: not to pause screen capture when Chrome is put to background

content/renderer/media/media_stream_dispatcher.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_MEDIA_STREAM_DISPATCHER_H_
 #define CONTENT_RENDERER_MEDIA_MEDIA_STREAM_DISPATCHER_H_
 
 #include <list>
 #include <map>
 #include <memory>
@@ skipping 57 matching lines @@
   virtual void CancelOpenDevice(
       int request_id,
       const base::WeakPtr<MediaStreamDispatcherEventHandler>& event_handler);
 
   // Close a started device. |label| is provided in OnDeviceOpened.
   void CloseDevice(const std::string& label);
 
   // This method is called when the stream is started successfully.
   void OnStreamStarted(const std::string& label);
 
+  // Get all the media devices of video capture, e.g. webcam. This is the set
+  // of devices that should be suspended when the content frame is no longer
+  // being shown to the user.
+  void GetNonScreenCaptureDevices(StreamDeviceInfoArray* video_array);
+
   // Check if the label is a valid stream.
   virtual bool IsStream(const std::string& label);
   // Get the video session_id given a label. The label identifies a stream.
   // index is the index in the video_device_array of the stream.
   virtual int video_session_id(const std::string& label, int index);
   // Returns an audio session_id given a label and an index.
   virtual int audio_session_id(const std::string& label, int index);
 
  protected:
   int GetNextIpcIdForTest() { return next_ipc_id_; }
 
  private:
   FRIEND_TEST_ALL_PREFIXES(MediaStreamDispatcherTest, BasicVideoDevice);
   FRIEND_TEST_ALL_PREFIXES(MediaStreamDispatcherTest, TestFailure);
   FRIEND_TEST_ALL_PREFIXES(MediaStreamDispatcherTest, CancelGenerateStream);
+  FRIEND_TEST_ALL_PREFIXES(MediaStreamDispatcherTest,
+                           GetNonScreenCaptureDevices);
 
   struct Request;
 
   // Private class for keeping track of opened devices and who have
   // opened it.
   struct Stream;
 
   // RenderFrameObserver override.
   void OnDestruct() override;
   bool Send(IPC::Message* message) override;
@@ skipping 27 matching lines @@
   // been canceled.
   typedef std::list<Request> RequestList;
   RequestList requests_;
 
   DISALLOW_COPY_AND_ASSIGN(MediaStreamDispatcher);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_MEDIA_MEDIA_STREAM_DISPATCHER_H_