MacViews a11y: Sync VoiceOver cursor with keyboard focus.

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"
 #include "base/strings/sys_string_conversions.h"
@@ skipping 1344 matching lines @@
     return @[ hostedView_->GetNativeViewAccessible() ];
   }
 
   return [super accessibilityAttributeValue:attribute];
 }
 
 - (id)accessibilityHitTest:(NSPoint)point {
   return [hostedView_->GetNativeViewAccessible() accessibilityHitTest:point];
 }
 
+- (id)accessibilityFocusedUIElement {
+  if (!hostedView_)
+    return nil;
+  return [hostedView_->GetNativeViewAccessible() accessibilityFocusedUIElement];
+}
+
 @end