Suppress the exception thrown when responding to message with no response callback.

chrome/test/data/extensions/hotword/test.js

Index: chrome/test/data/extensions/hotword/test.js
diff --git a/chrome/test/data/extensions/api_test/file_manager_browsertest/gallery/background.js b/chrome/test/data/extensions/hotword/test.js
similarity index 62%
copy from chrome/test/data/extensions/api_test/file_manager_browsertest/gallery/background.js
copy to chrome/test/data/extensions/hotword/test.js
index 94838a34d1f3e1c5c665a14db3d2d1a9945cf266..a252c697c026bb2d963b8a31bd39a445c9eaf16a 100644
--- a/chrome/test/data/extensions/api_test/file_manager_browsertest/gallery/background.js
+++ b/chrome/test/data/extensions/hotword/test.js
@@ -2,8 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-'use strict';
-
+// Send a WAKE_UP command to the hotword helper extension.
 chrome.runtime.sendMessage(
-    'nlkncpkkdoccmpiclbokaimcnedabhhm',
-    {name: 'testResourceLoaded'});
+    'dnhpdliibojhegemfjheidglijccjfmc',
+    {type: 'wu'});