Ensure that zoom in/out works in Chrome OS mode on Windows 7+.

win8/metro_driver/chrome_app_view_ash.cc

 // Copyright (c) 2012 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.
 
 #include "win8/metro_driver/stdafx.h"
 #include "win8/metro_driver/chrome_app_view_ash.h"
 
 #include <corewindow.h>
 #include <shellapi.h>
 #include <windows.foundation.h>
@@ skipping 1142 matching lines @@
 
 HRESULT ChromeAppViewAsh::OnWheel(
     winui::Core::ICoreWindow* sender,
     winui::Core::IPointerEventArgs* args) {
   PointerInfoHandler pointer(metro_dpi_scale_, win32_dpi_scale_);
   HRESULT hr = pointer.Init(args);
   if (FAILED(hr))
     return hr;
   DCHECK(pointer.IsMouse());
   SendMouseButton(pointer.x(), pointer.y(), pointer.wheel_delta(),
-                  ui::ET_MOUSEWHEEL, ui::EF_NONE, ui::EF_NONE,
+                  ui::ET_MOUSEWHEEL, GetKeyboardEventFlags(), ui::EF_NONE,
                   pointer.is_horizontal_wheel());
   return S_OK;
 }
 
 HRESULT ChromeAppViewAsh::OnKeyDown(
     winui::Core::ICoreWindow* sender,
     winui::Core::IKeyEventArgs* args) {
   winsys::VirtualKey virtual_key;
   HRESULT hr = args->get_VirtualKey(&virtual_key);
   if (FAILED(hr))
@@ skipping 222 matching lines @@
   mswr::ComPtr<winapp::Core::ICoreApplicationExit> app_exit;
   CheckHR(core_app.As(&app_exit));
   globals.app_exit = app_exit.Detach();
 }
 
 IFACEMETHODIMP
 ChromeAppViewFactory::CreateView(winapp::Core::IFrameworkView** view) {
   *view = mswr::Make<ChromeAppViewAsh>().Detach();
   return (*view) ? S_OK :  E_OUTOFMEMORY;
 }