fix "IME changed" notification uses a wrong field of IME

ash/system/tray/system_tray_delegate.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_TRAY_SYSTEM_TRAY_DELEGATE_H_
 #define ASH_SYSTEM_TRAY_SYSTEM_TRAY_DELEGATE_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 74 matching lines @@
 typedef std::vector<IMEPropertyInfo> IMEPropertyInfoList;
 
 struct ASH_EXPORT IMEInfo {
   IMEInfo();
   ~IMEInfo();
 
   bool selected;
   bool third_party;
   std::string id;
   string16 name;
+  string16 medium_name;
   string16 short_name;
 };
 
 typedef std::vector<IMEInfo> IMEInfoList;
 
 class VolumeControlDelegate;
 
 class SystemTrayDelegate {
  public:
   virtual ~SystemTrayDelegate() {}
@@ skipping 167 matching lines @@
 
   // Sets VolumeControlDelegate.
   virtual void SetVolumeControlDelegate(
       scoped_ptr<VolumeControlDelegate> delegate) = 0;
 
 };
 
 }  // namespace ash
 
 #endif  // ASH_SYSTEM_TRAY_SYSTEM_TRAY_DELEGATE_H_