[Mac] Retain location bar focus on switching to fullscreen and back.

chrome/browser/ui/cocoa/toolbar/toolbar_controller.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.
 
 #import "chrome/browser/ui/cocoa/toolbar/toolbar_controller.h"
 
 #include <sys/stat.h>
 #include <algorithm>
 
 #include "base/debug/crash_logging.h"
@@ skipping 580 matching lines @@
 - (LocationBarViewMac*)locationBarBridge {
   return locationBarView_.get();
 }
 
 - (void)locationBarWasAddedToWindow {
   // Allow the |locationBarView_| to update itself to match the browser window
   // theme.
   locationBarView_->OnAddedToWindow();
 }
 
+- (BOOL)locationBarHasFocus {
+  return [autocompleteTextFieldEditor_ window] != nil;
+}
+
 - (void)focusLocationBar:(BOOL)selectAll {
   if (locationBarView_.get()) {
     locationBarView_->FocusLocation(selectAll ? true : false);
   }
 }
 
 // Called when the state for a command changes to |enabled|. Update the
 // corresponding UI element.
 - (void)enabledStateChangedForCommand:(int)command enabled:(bool)enabled {
   NSButton* button = nil;
@@ skipping 498 matching lines @@
 - (void)hideDropURLsIndicatorInView:(NSView*)view {
   // Do nothing.
 }
 
 // (URLDropTargetController protocol)
 - (BOOL)isUnsupportedDropData:(id<NSDraggingInfo>)info {
   return drag_util::IsUnsupportedDropData(profile_, info);
 }
 
 @end