[VideoPlayer] Browser tests for new separated video player app

chrome/browser/resources/video_player/js/background.js

Index: chrome/browser/resources/video_player/js/background.js
diff --git a/chrome/browser/resources/video_player/js/background.js b/chrome/browser/resources/video_player/js/background.js
index 0ec6bdaaea6e84f133a63ea64d8ecd6c1226c6d7..28ed41eda0ee454d0e90e1288456bc3c7c930bc7 100644
--- a/chrome/browser/resources/video_player/js/background.js
+++ b/chrome/browser/resources/video_player/js/background.js
@@ -4,6 +4,12 @@
 
 'use strict';
 
+
+// Stores the app windows OLNY for test purpose.
+// We SHOULD NOT use it as it is except for test, since the files which have
+// the same name will be overridden each other.
+var appWindowsForTest = {};
+
 chrome.app.runtime.onLaunched.addListener(function(launchData) {
   if (!launchData || !launchData.items || launchData.items.length == 0)
     return;
@@ -26,6 +32,9 @@ function open(url, title) {
     minHeight: 100
   },
   function(createdWindow) {
+    // Stores the window for test purpose.
+    appWindowsForTest[title] = createdWindow;
+
     createdWindow.setIcon('images/200/icon.png');
     createdWindow.contentWindow.videoUrl = url;
     createdWindow.contentWindow.videoTitle = title;