Test wallpaper picker app could launch in dev and stable channel

chrome/browser/resources/chromeos/wallpaper_manager/js/util.js

 // Copyright (c) 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.
 
 var WallpaperUtil = {};
 
 /**
  * Saves value to local storage that associates with key.
  * @param {string} key The key that associates with value.
  * @param {string} value The value to save to local storage.
@@ skipping 86 matching lines @@
         chrome.wallpaperPrivate.setWallpaper(xhr.response, layout, url,
                                              onSuccess);
         self.saveWallpaperInfo(url, layout,
                                Constants.WallpaperSourceEnum.Online);
       } else {
         onFailure();
       }
     }, onFailure);
   });
 };
+
+/**
+ * Runs chrome.test.sendMessage in test environment. Does nothing if running
+ * in production environment.
+ *
+ * @param {string} message Test message to send.
+ */
+WallpaperUtil.testSendMessage = function(message) {
+  var test = chrome.test || window.top.chrome.test;
+  if (test)
+    test.sendMessage(message);
+};