Remove base/win/metro.{cc|h} and some associated code

chrome/browser/ui/cocoa/browser_window_factory_cocoa.mm

 // Copyright (c) 2010 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 "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/browser_window.h"
 #include "chrome/browser/ui/cocoa/browser_window_controller.h"
 
 // Create the controller for the Browser, which handles loading the browser
 // window from the nib. The controller takes ownership of |browser|.
 // static
 BrowserWindow* BrowserWindow::CreateBrowserWindow(Browser* browser) {
   BrowserWindowController* controller =
       [[BrowserWindowController alloc] initWithBrowser:browser];
   return [controller browserWindow];
 }
-
-// static
-chrome::HostDesktopType BrowserWindow::AdjustHostDesktopType(
-    chrome::HostDesktopType desktop_type) {
-  return desktop_type;
-}