Do not kill renderer when enumerateDevices is called from about:blank.

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 <stddef.h>
 
 #include <utility>
 #include <vector>
@@ skipping 99 matching lines @@
     const url::Origin& security_origin,
     const EnumerateDevicesCallback& client_callback) {
   DCHECK_CURRENTLY_ON(BrowserThread::IO);
 
   if (!request_audio_input && !request_video_input && !request_audio_output) {
     bad_message::ReceivedBadMessage(
         render_process_id_, bad_message::MDDH_INVALID_DEVICE_TYPE_REQUEST);
     return;
   }
 
+  // Ignore requests from unique origins, but do not crash the renderer.
+  if (security_origin.unique())
+    return;
+
   if (!MediaStreamManager::IsOriginAllowed(render_process_id_,
                                            security_origin)) {
     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;
@@ skipping 151 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