New method: InputMethod::IsCandidatePopupOpen()

ui/base/ime/input_method.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 UI_BASE_IME_INPUT_METHOD_H_
 #define UI_BASE_IME_INPUT_METHOD_H_
 
 #include <string>
 
 #include "base/basictypes.h"
@@ skipping 129 matching lines @@
   // is not active.
   virtual bool IsActive() = 0;
 
   // Gets the text input type of the focused text input client. Returns
   // ui::TEXT_INPUT_TYPE_NONE if there is no focused client.
   virtual TextInputType GetTextInputType() const = 0;
 
   // Checks if the focused text input client supports inline composition.
   virtual bool CanComposeInline() const = 0;
 
+  // Returns true if a candidate window (or IME suggest, etc.) is open.
+  // Returns false if no popup window is open or the detection of IME popups
+  // is not supported.
+  virtual bool IsPopupOpen() const = 0;

[Seigo Nonaka, 2013/06/19 09:15:51]

IsPopupOpen seems not clear for me.
How about IsCandidateWindowOpen or IsInputMethodUIActive?

By the way, is it okay to get only open or not?
I guess you are trying to integrate omnibox suggestion and candidate window.
introducing observer is more helpful?

[Yuki, 2013/06/19 09:35:54]

For name, I'd like to support in near future not only candidate windows, but
also IME suggest or anything similar.  So I thought "CandidateWindow" is too
specific.  From the view point of UI component, I think it's best to say
"Popup".  I'd like to cover any sort of popups, which would conflict with
Omnibox popup.

For observer, it's not helpful this time.  At
OmniboxPopupContentsView::UpdatePopupAppearance(), I'd like to check if any IME
popups are open or not.  So a simple getter method is more useful than a
observer.

+
   // Management of the observer list.
   virtual void AddObserver(InputMethodObserver* observer) = 0;
   virtual void RemoveObserver(InputMethodObserver* observer) = 0;
 };
 
 }  // namespace ui
 
 #endif  // UI_BASE_IME_INPUT_METHOD_H_