MacViews: Mark key down event as handled when consumed by the IME.

ui/views/cocoa/bridged_content_view.mm

 // Copyright 2014 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.
 
 #import "ui/views/cocoa/bridged_content_view.h"
 
 #include "base/logging.h"
 #import "base/mac/mac_util.h"
 #import "base/mac/scoped_nsobject.h"
 #import "base/mac/sdk_forward_declarations.h"
@@ skipping 1394 matching lines @@
   // Add a black underline with a transparent background to the composition
   // text. TODO(karandeepb): On Cocoa textfields, the target clause of the
   // composition has a thick underlines. The composition text also has
   // discontinous underlines for different clauses. This is also supported in
   // the Chrome renderer. Add code to extract underlines from |text| once our
   // render text implementation supports thick underlines and discontinous
   // underlines for consecutive characters. See http://crbug.com/612675.
   composition.underlines.push_back(ui::CompositionUnderline(
       0, [text length], SK_ColorBLACK, false, SK_ColorTRANSPARENT));
   textInputClient_->SetCompositionText(composition);
+  keyDownEvent_ = nil;  // Handled.
 }
 
 - (void)unmarkText {
-  if (textInputClient_)
-    textInputClient_->ConfirmCompositionText();
+  if (!textInputClient_)
+    return;
+
+  textInputClient_->ConfirmCompositionText();
+  keyDownEvent_ = nil;  // Handled.
 }
 
 - (NSArray*)validAttributesForMarkedText {
   return @[];
 }
 
 // NSUserInterfaceValidations protocol implementation.
 
 - (BOOL)validateUserInterfaceItem:(id<NSValidatedUserInterfaceItem>)item {
   ui::TextEditCommand command = GetTextEditCommandForMenuAction([item action]);
@@ skipping 46 matching lines @@
   return [hostedView_->GetNativeViewAccessible() accessibilityHitTest:point];
 }
 
 - (id)accessibilityFocusedUIElement {
   if (!hostedView_)
     return nil;
   return [hostedView_->GetNativeViewAccessible() accessibilityFocusedUIElement];
 }
 
 @end