Set display mode for extensions::AppWindow

chrome/test/data/extensions/api_test/fullscreen/mq_display_mode/window.js

+// Copyright (c) 2015 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.
+function checkWindowRestored() {
+  var standalone = matchMedia( '(display-mode: standalone)' );
+  chrome.test.assertTrue(standalone.matches,
+    "Display mode of the restored window is 'standalone'");
+
+  chrome.test.succeed();
+}
+
+function checkWindowFullscreened() {
+  var fullscreen = matchMedia( '(display-mode: fullscreen)' );
+  chrome.test.assertTrue(fullscreen.matches,
+    "Display mode of the fullscreened window is 'fullscreen'");
+
+  window.onresize = checkWindowRestored;
+  chrome.app.window.current().restore();
+}
+
+window.onload = function() {
+  function checkDisplayModeMediaFeature() {
+    var standalone = matchMedia( '(display-mode: standalone)' );
+    chrome.test.assertTrue(standalone.matches,
+                           "Initially display mode is 'standalone'");
+    window.onresize = checkWindowFullscreened;
+    chrome.app.window.current().fullscreen();
+  };
+  chrome.test.runTests([checkDisplayModeMediaFeature]);
+}