Workaround a nasty ibus issue.

chrome/browser/renderer_host/gtk_im_context_wrapper.h

 // Copyright (c) 2010 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 CHROME_BROWSER_RENDERER_HOST_GTK_IM_CONTEXT_WRAPPER_H_
 #define CHROME_BROWSER_RENDERER_HOST_GTK_IM_CONTEXT_WRAPPER_H_
 #pragma once
 
 #include <gdk/gdk.h>
 #include <pango/pango-attributes.h>
@@ skipping 52 matching lines @@
 
   void ConfirmComposition();
 
  private:
   // For unit tests.
   class GtkIMContextWrapperTest;
   FRIEND_TEST_ALL_PREFIXES(GtkIMContextWrapperTest, ExtractCompositionInfo);
 
   // Check if a text needs commit by forwarding a char event instead of
   // by confirming as a composition text.
-  bool NeedCommitByForwardingCharEvent();
+  bool NeedCommitByForwardingCharEvent() const;
+
+  // Check if the input method returned any result, eg. preedit and commit text.
+  bool HasInputMethodResult() const;
 
   void ProcessFilteredKeyPressEvent(NativeWebKeyboardEvent* wke);
   void ProcessUnfilteredKeyPressEvent(NativeWebKeyboardEvent* wke);
 
   // Processes result returned from input method after filtering a key event.
   // |filtered| indicates if the key event was filtered by the input method.
   void ProcessInputMethodResult(const GdkEventKey* event, bool filtered);
 
   // Real code of "commit" signal handler.
   void HandleCommit(const string16& text);
@@ skipping 115 matching lines @@
 
   // Stores a copy of the most recent commit text received by commit signal
   // handler.
   string16 commit_text_;
 
   // If it's true then the next "commit" signal will be suppressed.
   // It's only used to workaround http://crbug.com/50485.
   // TODO(suzhe): Remove it after input methods get fixed.
   bool suppress_next_commit_;
 
+  // Information of the last key event, for working around
+  // http://crosbug.com/6582
+  int last_key_code_;
+  bool last_key_was_up_;
+  bool last_key_filtered_no_result_;
+
   DISALLOW_COPY_AND_ASSIGN(GtkIMContextWrapper);
 };
 
 #endif  // CHROME_BROWSER_RENDERER_HOST_GTK_IM_CONTEXT_WRAPPER_H_