Do not consume Alt-Shift-Up event for IME switch.

chromeos/ime/input_method_manager.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 CHROMEOS_IME_INPUT_METHOD_MANAGER_H_
 #define CHROMEOS_IME_INPUT_METHOD_MANAGER_H_
 
 #include <map>
 #include <string>
 #include <vector>
@@ skipping 159 matching lines @@
   // layout, change the caps lock status, and set the auto repeat rate/interval.
   virtual ImeKeyboard* GetImeKeyboard() = 0;
 
   // Returns an InputMethodUtil object.
   virtual InputMethodUtil* GetInputMethodUtil() = 0;
 
   // Returns a ComponentExtentionIMEManager object.
   virtual ComponentExtensionIMEManager* GetComponentExtensionIMEManager() = 0;
 
   // Switches the current input method (or keyboard layout) to the next one.
-  virtual bool SwitchToNextInputMethod() = 0;
+  virtual void SwitchToNextInputMethod() = 0;
 
   // Switches the current input method (or keyboard layout) to the previous one.
   virtual bool SwitchToPreviousInputMethod(
       const ui::Accelerator& accelerator) = 0;
 
   // Switches to an input method (or keyboard layout) which is associated with
   // the |accelerator|.
   virtual bool SwitchInputMethod(const ui::Accelerator& accelerator) = 0;
 
   // If keyboard layout can be uset at login screen
   virtual bool IsLoginKeyboard(const std::string& layout) const = 0;
 
   // Migrates the input method id to extension-based input method id.
   virtual bool MigrateInputMethods(
       std::vector<std::string>* input_method_ids) = 0;
 };
 
 }  // namespace input_method
 }  // namespace chromeos
 
 #endif  // CHROMEOS_IME_INPUT_METHOD_MANAGER_H_