When we get a IME_CANCEL_COMPOSITION event on OSX, clear the

chrome/browser/renderer_host/render_widget_host_view_mac.mm

 // 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.
 
 #include <QuartzCore/QuartzCore.h>
 
 #include "chrome/browser/renderer_host/render_widget_host_view_mac.h"
 
 #include "app/surface/io_surface_support_mac.h"
 #import "base/chrome_application_mac.h"
@@ skipping 299 matching lines @@
 }
 
 void RenderWidgetHostViewMac::SetIsLoading(bool is_loading) {
   is_loading_ = is_loading;
   UpdateCursorIfOverSelf();
 }
 
 void RenderWidgetHostViewMac::IMEUpdateStatus(int control,
                                               const gfx::Rect& caret_rect) {
   // Reset the IME state and finish an ongoing composition in the renderer.
-  if (control == IME_DISABLE || control == IME_COMPLETE_COMPOSITION)
+  if (control == IME_DISABLE || control == IME_COMPLETE_COMPOSITION ||
+      control == IME_CANCEL_COMPOSITION) {
     [cocoa_view_ cancelComposition];
+  }
 
   // We need to convert the coordinate of the cursor rectangle sent from the
   // renderer and save it. Our IME backend uses a coordinate system whose
   // origin is the upper-left corner of this view. On the other hand, Cocoa
   // uses a coordinate system whose origin is the lower-left corner of this
   // view. So, we convert the cursor rectangle and save it.
   [cocoa_view_ setCaretRect:[cocoa_view_ RectToNSRect:caret_rect]];
 }
 
 void RenderWidgetHostViewMac::DidPaintBackingStoreRects(
@@ skipping 1486 matching lines @@
   // doesn't call any NSTextInput functions, such as setMarkedText or
   // insertText. So, we need to send an IPC message to a renderer so it can
   // delete the composition node.
   NSInputManager *currentInputManager = [NSInputManager currentInputManager];
   [currentInputManager markedTextAbandoned:self];
 
   [self unmarkText];
 }
 
 @end