Update appearance of omnibox focus for MD.

chrome/browser/ui/cocoa/omnibox/omnibox_view_mac.mm

 // Copyright (c) 2012 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 "chrome/browser/ui/cocoa/omnibox/omnibox_view_mac.h"
 
 #include <Carbon/Carbon.h>  // kVK_Return
 
 #include "base/mac/foundation_util.h"
 #include "base/memory/ptr_util.h"
@@ skipping 902 matching lines @@
         return true;
       }
     }
   }
 
   return false;
 }
 
 void OmniboxViewMac::OnSetFocus(bool control_down) {
   model()->OnSetFocus(control_down);
-  controller()->OnSetFocus();
+  // Update the keyword and search hint states.
+  controller()->OnChanged();
 }
 
 void OmniboxViewMac::OnKillFocus() {
   // Tell the model to reset itself.
   model()->OnWillKillFocus();
   model()->OnKillFocus();
 }
 
 void OmniboxViewMac::OnMouseDown(NSInteger button_number) {
   // Restore caret visibility whenever the user clicks in the the omnibox. This
@@ skipping 199 matching lines @@
 
 NSUInteger OmniboxViewMac::GetTextLength() const {
   return [field_ currentEditor] ?  [[[field_ currentEditor] string] length] :
                                    [[field_ stringValue] length];
 }
 
 bool OmniboxViewMac::IsCaretAtEnd() const {
   const NSRange selection = GetSelectedRange();
   return NSMaxRange(selection) == GetTextLength();
 }