Implement CancelUserMediaRequest for the browser part

content/browser/renderer_host/media/media_stream_device_settings.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_device_settings.h"
 
 #include <algorithm>
 
 #include "base/bind.h"
 #include "base/callback.h"
@@ skipping 116 matching lines @@
     // Request with this id already exists.
     requester_->SettingsError(label);
     return;
   }
 
   // Create a new request.
   requests_.insert(std::make_pair(label, new MediaStreamDeviceSettingsRequest(
       render_process_id, render_view_id, security_origin, request_options)));
 }
 
+void MediaStreamDeviceSettings::RemovePendingCaptureRequest(
+    const std::string& label) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
+
+  SettingsRequests::iterator request_it = requests_.find(label);
+  if (request_it != requests_.end()) {
+    MediaStreamDeviceSettingsRequest* request = request_it->second;
+    requests_.erase(request_it);
+    delete request;
+  }
+}
+
 void MediaStreamDeviceSettings::AvailableDevices(
     const std::string& label,
     MediaStreamType stream_type,
     const StreamDeviceInfoArray& devices) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 
   SettingsRequests::iterator request_it = requests_.find(label);
   DCHECK(request_it != requests_.end());
 
   // Add the answer for the request.
@@ skipping 172 matching lines @@
   BrowserThread::PostTask(
       BrowserThread::UI, FROM_HERE,
       base::Bind(
           &content::ContentBrowserClient::RequestMediaAccessPermission,
           base::Unretained(content::GetContentClient()->browser()),
           request, callback));
 
 }
 
 }  // namespace media_stream