Let Contraints Controll Mute/Unmute Audio Local Playback For Desktop Sharing

content/browser/media/capture/web_contents_video_capture_device.cc

 // 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.
 //
 // Implementation notes: This needs to work on a variety of hardware
 // configurations where the speed of the CPU and GPU greatly affect overall
 // performance. Spanning several threads, the process of capturing has been
 // split up into four conceptual stages:
 //
 //   1. Reserve Buffer: Before a frame can be captured, a slot in the client's
@@ skipping 932 matching lines @@
           std::unique_ptr<media::VideoCaptureMachine>(
               new WebContentsCaptureMachine(render_process_id,
                                             main_render_frame_id,
                                             enable_auto_throttling)))) {}
 
 WebContentsVideoCaptureDevice::~WebContentsVideoCaptureDevice() {
   DVLOG(2) << "WebContentsVideoCaptureDevice@" << this << " destroying.";
 }
 
 // static
-media::VideoCaptureDevice* WebContentsVideoCaptureDevice::Create(
-    const std::string& device_id) {
+std::unique_ptr<media::VideoCaptureDevice>
+WebContentsVideoCaptureDevice::Create(const std::string& device_id) {
   // Parse device_id into render_process_id and main_render_frame_id.
-  int render_process_id = -1;
-  int main_render_frame_id = -1;
-  if (!WebContentsMediaCaptureId::ExtractTabCaptureTarget(
-          device_id, &render_process_id, &main_render_frame_id)) {
+  WebContentsMediaCaptureId media_id;
+  if (!WebContentsMediaCaptureId::Parse(device_id, &media_id)) {
     return NULL;
   }
 
-  return new WebContentsVideoCaptureDevice(
-      render_process_id, main_render_frame_id,
-      WebContentsMediaCaptureId::IsAutoThrottlingOptionSet(device_id));
+  return std::unique_ptr<media::VideoCaptureDevice>(

[Sergey Ulanov, 2016/10/12 22:21:01]

nit:: use base::MakeUnique<WebContentsVideoCaptureDevice>

[qiangchen, 2016/10/12 22:49:54]

Not work. As media::VideoCaptureDevice is an abstract class, and it does not
allow base::MakeUnique<media::VideoCaptureDevice>. 

+      new WebContentsVideoCaptureDevice(media_id.render_process_id,
+                                        media_id.main_render_frame_id,
+                                        media_id.enable_auto_throttling));
 }
 
 void WebContentsVideoCaptureDevice::AllocateAndStart(
     const media::VideoCaptureParams& params,
     std::unique_ptr<Client> client) {
   DVLOG(1) << "Allocating " << params.requested_format.frame_size.ToString();
   core_->AllocateAndStart(params, std::move(client));
 }
 
 void WebContentsVideoCaptureDevice::RequestRefreshFrame() {
   core_->RequestRefreshFrame();
 }
 
 void WebContentsVideoCaptureDevice::StopAndDeAllocate() {
   core_->StopAndDeAllocate();
 }
 
 }  // namespace content