Attempting to reland the Overview Button Change.

ash/system/status_area_widget.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 ASH_SYSTEM_STATUS_AREA_WIDGET_H_
 #define ASH_SYSTEM_STATUS_AREA_WIDGET_H_
 
 #include "ash/ash_export.h"
 #include "ash/shelf/shelf_types.h"
 #include "ash/system/user/login_status.h"
 #include "ui/views/widget/widget.h"
 
 namespace ash {
 
+class OverviewButtonTray;
 class ShellDelegate;
 class SystemTray;
 class WebNotificationTray;
 
 namespace internal {
 
 class StatusAreaWidgetDelegate;
 #if defined(OS_CHROMEOS)
 class LogoutButtonTray;
 class VirtualKeyboardTray;
@@ skipping 24 matching lines @@
   // notification tray.
   void UpdateAfterLoginStatusChange(user::LoginStatus login_status);
 
   internal::StatusAreaWidgetDelegate* status_area_widget_delegate() {
     return status_area_widget_delegate_;
   }
   SystemTray* system_tray() { return system_tray_; }
   WebNotificationTray* web_notification_tray() {
     return web_notification_tray_;
   }
+  OverviewButtonTray* overview_button_tray() {
+    return overview_button_tray_;
+  }
 
   user::LoginStatus login_status() const { return login_status_; }
 
   // Returns true if the shelf should be visible. This is used when the
   // shelf is configured to auto-hide and test if the shelf should force
   // the shelf to remain visible.
   bool ShouldShowShelf() const;
 
   // True if any message bubble is shown.
   bool IsMessageBubbleShown() const;
 
   // Overridden from views::Widget:
   virtual void OnNativeWidgetActivationChanged(bool active) OVERRIDE;
 
  private:
   void AddSystemTray();
   void AddWebNotificationTray();
 #if defined(OS_CHROMEOS)
   void AddLogoutButtonTray();
   void AddVirtualKeyboardTray();
 #endif
+  void AddOverviewButtonTray();
 
   // Weak pointers to View classes that are parented to StatusAreaWidget:
   internal::StatusAreaWidgetDelegate* status_area_widget_delegate_;
+  OverviewButtonTray* overview_button_tray_;
   SystemTray* system_tray_;
   WebNotificationTray* web_notification_tray_;
 #if defined(OS_CHROMEOS)
   LogoutButtonTray* logout_button_tray_;
   VirtualKeyboardTray* virtual_keyboard_tray_;
 #endif
   user::LoginStatus login_status_;
 
   DISALLOW_COPY_AND_ASSIGN(StatusAreaWidget);
 };
 
 }  // namespace internal
 }  // namespace ash
 
 #endif  // ASH_SYSTEM_STATUS_AREA_WIDGET_H_