Fix race in MediaDevicesPermissionChecker.

content/browser/renderer_host/media/media_devices_dispatcher_host.cc

 // Copyright 2016 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_devices_dispatcher_host.h"
 
 #include <utility>
 #include <vector>
 
 #include "base/bind_helpers.h"
@@ skipping 48 matching lines @@
 MediaDevicesDispatcherHost::MediaDevicesDispatcherHost(
     int render_process_id,
     int routing_id,
     const std::string& device_id_salt,
     MediaStreamManager* media_stream_manager)
     : render_process_id_(render_process_id),
       routing_id_(routing_id),
       device_id_salt_(device_id_salt),
       group_id_salt_(ResourceContext::CreateRandomMediaDeviceIDSalt()),
       media_stream_manager_(media_stream_manager),
+      permission_checker_(base::MakeUnique<MediaDevicesPermissionChecker>()),
       weak_factory_(this) {
   DCHECK_CURRENTLY_ON(BrowserThread::IO);
 }
 
 MediaDevicesDispatcherHost::~MediaDevicesDispatcherHost() {
   DCHECK_CURRENTLY_ON(BrowserThread::IO);
 }
 
 void MediaDevicesDispatcherHost::EnumerateDevices(
     bool request_audio_input,
@@ skipping 14 matching lines @@
     bad_message::ReceivedBadMessage(render_process_id_,
                                     bad_message::MDDH_UNAUTHORIZED_ORIGIN);
     return;
   }
 
   MediaDevicesManager::BoolDeviceTypes devices_to_enumerate;
   devices_to_enumerate[MEDIA_DEVICE_TYPE_AUDIO_INPUT] = request_audio_input;
   devices_to_enumerate[MEDIA_DEVICE_TYPE_VIDEO_INPUT] = request_video_input;
   devices_to_enumerate[MEDIA_DEVICE_TYPE_AUDIO_OUTPUT] = request_audio_output;
 
-  permission_checker_.CheckPermissions(
+  permission_checker_->CheckPermissions(
       devices_to_enumerate, render_process_id_, routing_id_, security_origin,
       base::Bind(&MediaDevicesDispatcherHost::DoEnumerateDevices,
                  weak_factory_.GetWeakPtr(), devices_to_enumerate,
                  security_origin, client_callback));
 }
 
 void MediaDevicesDispatcherHost::SetPermissionChecker(
-    const MediaDevicesPermissionChecker& permission_checker) {
+    std::unique_ptr<MediaDevicesPermissionChecker> permission_checker) {
   DCHECK_CURRENTLY_ON(BrowserThread::IO);
-  permission_checker_ = permission_checker;
+  DCHECK(permission_checker);
+  permission_checker_ = std::move(permission_checker);
 }
 
 void MediaDevicesDispatcherHost::DoEnumerateDevices(
     const MediaDevicesManager::BoolDeviceTypes& requested_types,
     const url::Origin& security_origin,
     const EnumerateDevicesCallback& client_callback,
     const MediaDevicesManager::BoolDeviceTypes& has_permissions) {
   DCHECK_CURRENTLY_ON(BrowserThread::IO);
   media_stream_manager_->media_devices_manager()->EnumerateDevices(
       requested_types,
@@ skipping 17 matching lines @@
     for (const auto& device_info : enumeration[i]) {
       result[i].push_back(TranslateDeviceInfo(has_permissions[i],
                                               device_id_salt_, group_id_salt_,
                                               security_origin, device_info));
     }
   }
   client_callback.Run(result);
 }
 
 }  // namespace content