[win8] Force browsers created with Chrome in Metro mode to be on the Ash desktop.

chrome/browser/ui/views/frame/native_browser_frame_factory.h

 // 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.
 
 #ifndef CHROME_BROWSER_UI_VIEWS_FRAME_NATIVE_BROWSER_FRAME_FACTORY_H_
 #define CHROME_BROWSER_UI_VIEWS_FRAME_NATIVE_BROWSER_FRAME_FACTORY_H_
 
 #include "base/basictypes.h"
+#include "chrome/browser/ui/host_desktop.h"
 
 class BrowserFrame;
 class BrowserView;
 class NativeBrowserFrame;
 
 // Factory for creating a NativeBrowserFrame.
 class NativeBrowserFrameFactory {
  public:
   // Construct a platform-specific implementation of this interface.
   static NativeBrowserFrame* CreateNativeBrowserFrame(
       BrowserFrame* browser_frame,
       BrowserView* browser_view);
 
   // Sets the factory. Takes ownership of |new_factory|, deleting existing
   // factory. Use NULL to go back to default factory.
   static void Set(NativeBrowserFrameFactory* new_factory);
 
+  // Returns HOST_DESKTOP_TYPE_ASH on Windows when configured to allow browser
+  // windows only in Metro mode, otherwise |desktop_type|.
+  static chrome::HostDesktopType AdjustHostDesktopType(
+      chrome::HostDesktopType desktop_type);
+
   virtual NativeBrowserFrame* Create(BrowserFrame* browser_frame,
                                      BrowserView* browser_view);
 
  protected:
   NativeBrowserFrameFactory() {}
   virtual ~NativeBrowserFrameFactory() {}
 
+ private:
+  // For Chrome running on desktop platforms, returns true if the factory should
+  // create an ash browser frame for the provided |browser_view|.
+  static bool ShouldCreateForAshDesktop(BrowserView* browser_view);
+
   DISALLOW_COPY_AND_ASSIGN(NativeBrowserFrameFactory);
 };
 
 #endif  // CHROME_BROWSER_UI_VIEWS_FRAME_NATIVE_BROWSER_FRAME_FACTORY_H_