Cancels an ongoing IME composition when receiving an IME_CANCEL_COMPOSITION event on Windows.

This change just adds ImeInput::CancelIME() and use it when receiving an IME_CANCEL_COMPOSITION event. (I'm not sure it works well with all IMEs, though.)

BUG=9883
TEST=none
Review URL: http://codereview.chromium.org/2099012

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@48470 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 22 insertions, 3 deletions

diff --git a/chrome/browser/ime_input.cc b/chrome/browser/ime_input.cc
index 21b5229..3f60670 100644
--- a/chrome/browser/ime_input.cc
+++ b/chrome/browser/ime_input.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
+// 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.
 
@@ -304,6 +304,17 @@ void ImeInput::DisableIME(HWND window_handle) {
   ::ImmAssociateContextEx(window_handle, NULL, 0);
 }
 
+void ImeInput::CancelIME(HWND window_handle) {
+  if (is_composing_) {
+    HIMC imm_context = ::ImmGetContext(window_handle);
+    if (imm_context) {
+      ::ImmNotifyIME(imm_context, NI_COMPOSITIONSTR, CPS_CANCEL, 0);
+      ::ImmReleaseContext(window_handle, imm_context);
+    }
+    ResetComposition(window_handle);
+  }
+}
+
 void ImeInput::EnableIME(HWND window_handle,
                          const gfx::Rect& caret_rect,
                          bool complete) {
diff --git a/chrome/browser/ime_input.h b/chrome/browser/ime_input.h
index b1ebf4a..45fe21f 100644
--- a/chrome/browser/ime_input.h
+++ b/chrome/browser/ime_input.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
+// 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.
 
@@ -235,6 +235,12 @@ class ImeInput {
   //     Represents the window handle of the caller.
   void DisableIME(HWND window_handle);
 
+  // Cancels an ongoing composition of the IME attached to the given window.
+  // Parameters
+  //   * window_handle [in] (HWND)
+  //     Represents the window handle of the caller.
+  void CancelIME(HWND window_handle);
+
  protected:
   // Determines whether or not the given attribute represents a target
   // (a.k.a. a selection).
@@ -300,7 +306,7 @@ class ImeInput {
   // The rectangle of the input caret retrieved from a renderer process.
   gfx::Rect caret_rect_;
 
-  DISALLOW_EVIL_CONSTRUCTORS(ImeInput);
+  DISALLOW_COPY_AND_ASSIGN(ImeInput);
 };
 
 #endif  // CHROME_BROWSER_IME_INPUT_H_
diff --git a/chrome/browser/renderer_host/render_widget_host_view_win.cc b/chrome/browser/renderer_host/render_widget_host_view_win.cc
index b482b87..e195317 100644
--- a/chrome/browser/renderer_host/render_widget_host_view_win.cc
+++ b/chrome/browser/renderer_host/render_widget_host_view_win.cc
@@ -614,6 +614,8 @@ void RenderWidgetHostViewWin::IMEUpdateStatus(int control,
                                               const gfx::Rect& caret_rect) {
   if (control == IME_DISABLE) {
     ime_input_.DisableIME(m_hWnd);
+  } else if (control == IME_CANCEL_COMPOSITION) {
+    ime_input_.CancelIME(m_hWnd);
   } else {
     ime_input_.EnableIME(m_hWnd, caret_rect,
                          control == IME_COMPLETE_COMPOSITION);