[MacViews] Update AppWindow when the native window changes fullscreen state.

chrome/browser/ui/views/apps/chrome_native_app_window_views_mac.mm

 // Copyright 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.
 
 #import "chrome/browser/ui/views/apps/chrome_native_app_window_views_mac.h"
 
 #include "chrome/browser/apps/app_shim/extension_app_shim_handler_mac.h"
 #include "chrome/browser/ui/views/apps/app_window_native_widget_mac.h"
 #include "chrome/browser/ui/views/apps/native_app_window_frame_view_mac.h"
 
@@ skipping 41 matching lines @@
   UnhideWithoutActivation();
   ChromeNativeAppWindowViews::Activate();
 }
 
 void ChromeNativeAppWindowViewsMac::FlashFrame(bool flash) {
   apps::ExtensionAppShimHandler::RequestUserAttentionForWindow(
       app_window(), flash ? apps::APP_SHIM_ATTENTION_CRITICAL
                           : apps::APP_SHIM_ATTENTION_CANCEL);
 }
 
+void ChromeNativeAppWindowViewsMac::OnWidgetBoundsChanged(
+  views::Widget* widget,
+     const gfx::Rect& new_bounds) {
+  app_window()->UpdateOSFullscreenState(IsFullscreen());
+}
+
 void ChromeNativeAppWindowViewsMac::ShowWithApp() {
   is_hidden_with_app_ = false;
   if (!app_window()->is_hidden())
     ShowInactive();
 }
 
 void ChromeNativeAppWindowViewsMac::HideWithApp() {
   is_hidden_with_app_ = true;
   ChromeNativeAppWindowViews::Hide();
 }
 
 void ChromeNativeAppWindowViewsMac::UnhideWithoutActivation() {
   if (is_hidden_with_app_) {
     apps::ExtensionAppShimHandler::UnhideWithoutActivationForWindow(
         app_window());
     is_hidden_with_app_ = false;
   }
 }