Implement CancelUserMediaRequest for the browser part

content/browser/renderer_host/media/media_stream_manager.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.
 
 #include "content/browser/renderer_host/media/media_stream_manager.h"
 
 #include <list>
 
 #include "base/bind.h"
 #include "base/compiler_specific.h"
@@ skipping 196 matching lines @@
           }
         }
       }
       requests_.erase(it++);
     } else {
       ++it;
     }
   }
 }
 
+void MediaStreamManager::CancelGeneratedStream(const std::string& label) {

[wjia(left Chromium), 2012/06/06 06:18:21]

This would be MediaStreamManager::CancelGenerateStream.

Since this function could be called at any time during a stream is generated and
there are multiple steps to generate a stream, it would be great to take care
all cases. For example, this function is called when user has granted access
permission and device managers are trying to open devices. This patch takes care
of the case in which user has not granted access permission yet.

+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
+
+  DeviceRequests::iterator it = requests_.find(label);
+  if (it != requests_.end()) {
+    device_settings_->RemovePendingCaptureRequest(label);
+    requests_.erase(it);
+  }
+}
+
 void MediaStreamManager::StopGeneratedStream(const std::string& label) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
   // Find the request and close all open devices for the request.
   DeviceRequests::iterator it = requests_.find(label);
   if (it != requests_.end()) {
     for (StreamDeviceInfoArray::iterator audio_it =
          it->second.audio_devices.begin();
          audio_it != it->second.audio_devices.end(); ++audio_it) {
       audio_input_device_manager()->Close(audio_it->session_id);
     }
@@ skipping 429 matching lines @@
   if (stream_type == content::MEDIA_STREAM_DEVICE_TYPE_VIDEO_CAPTURE) {
     return video_capture_manager();
   } else if (stream_type == content::MEDIA_STREAM_DEVICE_TYPE_AUDIO_CAPTURE) {
     return audio_input_device_manager();
   }
   NOTREACHED();
   return NULL;
 }
 
 }  // namespace media_stream