Reverting this as it breaks (at least) the Windows Aura build.

chrome/browser/ui/views/aura/chrome_shell_delegate.h

 // Copyright (c) 2011 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_AURA_CHROME_SHELL_DELEGATE_H_
 #define CHROME_BROWSER_UI_VIEWS_AURA_CHROME_SHELL_DELEGATE_H_
 #pragma once
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/memory/scoped_ptr.h"
 #include "ui/aura_shell/launcher/launcher_types.h"
 #include "ui/aura_shell/shell_delegate.h"
 
+class StatusAreaHostAura;
 class Browser;
-class StatusAreaHostAura;
-
-namespace views {
-class View;
-}
 
 class ChromeShellDelegate : public aura_shell::ShellDelegate {
  public:
   ChromeShellDelegate();
   virtual ~ChromeShellDelegate();
 
-  static ChromeShellDelegate* instance() { return instance_; }
-
-  const views::View* GetStatusArea() const;
-
   // Returns whether a launcher item should be created for |browser|. If an item
   // should be created |type| is set to the launcher type to create.
   static bool ShouldCreateLauncherItemForBrowser(
       Browser* browser,
       aura_shell::LauncherItemType* type);
 
   // aura_shell::ShellDelegate overrides;
   virtual void CreateNewWindow() OVERRIDE;
   virtual views::Widget* CreateStatusArea() OVERRIDE;
   virtual void ShowApps() OVERRIDE;
   virtual void LauncherItemClicked(
       const aura_shell::LauncherItem& item) OVERRIDE;
   virtual bool ConfigureLauncherItem(aura_shell::LauncherItem* item) OVERRIDE;
 
  private:
-  static ChromeShellDelegate* instance_;
-
   scoped_ptr<StatusAreaHostAura> status_area_host_;
 
   DISALLOW_COPY_AND_ASSIGN(ChromeShellDelegate);
 };
 
 #endif  // CHROME_BROWSER_UI_VIEWS_AURA_CHROME_SHELL_DELEGATE_H_