[Win] Keep client area the same size as window when fullscreened.

chrome/test/data/extensions/platform_apps/window_api_interactive/test.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.
 
 var callbackPass = chrome.test.callbackPass;
 
 function testWindowGetsFocus(win) {
   // If the window is already focused, we are done.
   if (win.contentWindow.document.hasFocus()) {
     chrome.test.assertTrue(win.contentWindow.document.hasFocus(),
@@ skipping 214 matching lines @@
   chrome.test.runTests([
     function drawThenClearAttention() {
       chrome.app.window.create('test.html', {}, callbackPass(function(win) {
         win.drawAttention();
         win.clearAttention();
       }));
     }
   ]);
 }
 
+function testFullscreen() {
+  chrome.test.runTests([
+    function createFullscreen() {
+      chrome.app.window.create('test.html', {
+        state: 'fullscreen',
+      }, callbackPass(function (win) {
+        chrome.test.assertEq(win.contentWindow.screen.width,
+                             win.contentWindow.innerWidth);
+        chrome.test.assertEq(win.contentWindow.screen.height,
+                             win.contentWindow.innerHeight);
+      }));
+    }
+  ]);
+}
+
 chrome.app.runtime.onLaunched.addListener(function() {
   chrome.test.sendMessage('Launched', function(reply) {
     window[reply]();
   });
 });