Fix webrtcAudioPrivate API to handle requests from <webview>s.

chrome/browser/resources/hangout_services/thunk.js

 // Copyright 2013 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.
 
 chrome.runtime.onMessageExternal.addListener(
     function(message, sender, sendResponse) {
       function doSendResponse(value, errorString) {
         var error = null;
         if (errorString) {
           error = {};
@@ skipping 89 matching lines @@
           return true;
         } else if (method == 'logging.discard') {
           chrome.webrtcLoggingPrivate.discard(
               requestInfo, origin, doSendResponse);
           return true;
         } else if (method == 'getSinks') {
           chrome.webrtcAudioPrivate.getSinks(doSendResponse);
           return true;
         } else if (method == 'getActiveSink') {
           chrome.webrtcAudioPrivate.getActiveSink(
-              sender.tab.id, doSendResponse);
+              requestInfo, doSendResponse);
           return true;
         } else if (method == 'setActiveSink') {
           var sinkId = message['sinkId'];
           chrome.webrtcAudioPrivate.setActiveSink(
-              sender.tab.id, sinkId, doSendResponse);
+              requestInfo, sinkId, doSendResponse);
           return true;
         } else if (method == 'getAssociatedSink') {
           var sourceId = message['sourceId'];
           chrome.webrtcAudioPrivate.getAssociatedSink(
               origin, sourceId, doSendResponse);
           return true;
         } else if (method == 'isExtensionEnabled') {
           // This method is necessary because there may be more than one
           // version of this extension, under different extension IDs. By
           // first calling this method on the extension ID, the client can
@@ skipping 128 matching lines @@
     onSinksChangedPort(port);
   } else if (port.name == 'chooseDesktopMedia') {
     onChooseDesktopMediaPort(port);
   } else if (port.name == 'processCpu') {
     onProcessCpu(port);
   } else {
     // Unknown port type.
     port.disconnect();
   }
 });