Remove HostDesktopType from BrowserList::GetInstance()

chrome/browser/ui/host_desktop.h

 // 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.
 
 #ifndef CHROME_BROWSER_UI_HOST_DESKTOP_H_
 #define CHROME_BROWSER_UI_HOST_DESKTOP_H_
 
 #include "build/build_config.h"
 #include "ui/gfx/native_widget_types.h"
 
 class Browser;
 
 namespace chrome {
 
-// A value that specifies what desktop environment hosts a particular piece of
-// UI. You should almost never manually hardcode one of these enums manually,
-// please refer to the following document for details on getting the right
-// HostDesktopType:
-// http://sites.google.com/a/chromium.org/dev/developers/design-documents/aura/multi-desktop
+// TODO(scottmg): This file is being removed: http://crbug.com/558054.
 enum HostDesktopType {
   HOST_DESKTOP_TYPE_FIRST = 0,
 
   // The UI is hosted on the system native desktop.
   HOST_DESKTOP_TYPE_NATIVE = HOST_DESKTOP_TYPE_FIRST,
 
   // The UI is hosted in the synthetic Ash desktop.
 #if defined(OS_CHROMEOS)
   HOST_DESKTOP_TYPE_ASH = HOST_DESKTOP_TYPE_NATIVE,
 #else
@@ skipping 10 matching lines @@
 // Returns the type of host desktop most likely to be in use.  This is the one
 // most recently activated by the user.
 // You should almost never use this outside of tests, please refer to the
 // following document for details on getting the right HostDesktopType:
 // http://sites.google.com/a/chromium.org/dev/developers/design-documents/aura/multi-desktop
 HostDesktopType GetActiveDesktop();
 
 }  // namespace chrome
 
 #endif  // CHROME_BROWSER_UI_HOST_DESKTOP_H_