Stop using shell::GetInstance()->system_tray() in system tray items

ash/system/ime/tray_ime.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_IME_TRAY_IME_H_
 #define ASH_SYSTEM_IME_TRAY_IME_H_
 
 #include "ash/system/ime/ime_observer.h"
 #include "ash/system/tray/system_tray_item.h"
 
@@ skipping 11 matching lines @@
 class IMEDefaultView;
 class IMEDetailedView;
 class IMENotificationView;
 }
 
 class TrayItemView;
 
 class TrayIME : public SystemTrayItem,
                 public IMEObserver {
  public:
-  TrayIME();
+  explicit TrayIME(SystemTray* system_tray);
   virtual ~TrayIME();
 
  private:
   void UpdateTrayLabel(const IMEInfo& info, size_t count);
 
   // Overridden from SystemTrayItem.
   virtual views::View* CreateTrayView(user::LoginStatus status) OVERRIDE;
   virtual views::View* CreateDefaultView(user::LoginStatus status) OVERRIDE;
   virtual views::View* CreateDetailedView(user::LoginStatus status) OVERRIDE;
   virtual views::View* CreateNotificationView(
@@ skipping 16 matching lines @@
 
   bool message_shown_;
 
   DISALLOW_COPY_AND_ASSIGN(TrayIME);
 };
 
 }  // namespace internal
 }  // namespace ash
 
 #endif  // ASH_SYSTEM_IME_TRAY_IME_H_