Create a private API for controlling WebRTC's AEC3

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 184 matching lines @@
           return true;
         } else if (method == 'logging.startWebRtcEventLogging') {
           var seconds = message['seconds'] || 0;
           chrome.webrtcLoggingPrivate.startWebRtcEventLogging(
               requestInfo, origin, seconds, doSendResponse);
           return true;
         } else if (method == 'logging.stopWebRtcEventLogging') {
           chrome.webrtcLoggingPrivate.stopWebRtcEventLogging(
               requestInfo, origin, doSendResponse);
           return true;
+        } else if (method == 'setAudioExperiments') {
+          var experiments = message['experiments'];
+          chrome.webrtcAudioPrivate.setAudioExperiments(
+              requestInfo, origin, experiments);

[mnilsson, 2017/04/10 19:15:45]

Why not embed the doSendResponse as a callback method to setAudioExperiments
(like other methods in this file)? Wouldn't it otherwise be racy to know when
the experiments have actually been set?

[Henrik Grunell, 2017/04/11 06:49:39]

If the application needs to know exactly when it has been set then yes. (Or if
success/failure information is needed.) I don't see why that would be necessary
though. If it is, then by all means there should be a callback.

+          doSendResponse();
+          return false;
         }
 
         throw new Error('Unknown method: ' + method);
       } catch (e) {
         doSendResponse(null, e.name + ': ' + e.message);
       }
     }
 );
 
 // If Hangouts connects with a port named 'onSinksChangedListener', we
@@ skipping 105 matching lines @@
     onSinksChangedPort(port);
   } else if (port.name == 'chooseDesktopMedia') {
     onChooseDesktopMediaPort(port);
   } else if (port.name == 'processCpu') {
     onProcessCpu(port);
   } else {
     // Unknown port type.
     port.disconnect();
   }
 });