ash: Add a bluetooth entry in the uber tray.

ash/system/tray/tray_image_item.h

Index: ash/system/tray/tray_image_item.h
diff --git a/ash/system/tray/tray_image_item.h b/ash/system/tray/tray_image_item.h
index 7cc27bcaae3ed31b81d249504d9dc53e783d5ab7..844b4a647d1cbdaccf2d1b1ab35f8fea2a647f36 100644
--- a/ash/system/tray/tray_image_item.h
+++ b/ash/system/tray/tray_image_item.h
@@ -23,9 +23,8 @@ class TrayImageItem : public SystemTrayItem {
   views::ImageView* image_view() { return image_view_.get(); }
 
  protected:
-  virtual bool ShouldDisplay() = 0;
+  virtual bool InitialVisibility() = 0;
 
- private:
   // Overridden from SystemTrayItem.
   virtual views::View* CreateTrayView(user::LoginStatus status) OVERRIDE;
   virtual views::View* CreateDefaultView(user::LoginStatus status) OVERRIDE;
@@ -34,6 +33,7 @@ class TrayImageItem : public SystemTrayItem {
   virtual void DestroyDefaultView() OVERRIDE;
   virtual void DestroyDetailedView() OVERRIDE;
 
+ private:
   int resource_id_;
   scoped_ptr<views::ImageView> image_view_;