[Mac]Implement ViewID support. (third approach)

chrome/browser/cocoa/location_bar/autocomplete_text_field.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.
 
 #import "chrome/browser/cocoa/location_bar/autocomplete_text_field.h"
 
 #include "base/logging.h"
 #import "chrome/browser/cocoa/browser_window_controller.h"
 #import "chrome/browser/cocoa/location_bar/autocomplete_text_field_cell.h"
 #import "chrome/browser/cocoa/location_bar/autocomplete_text_field_editor.h"
 #import "chrome/browser/cocoa/toolbar_controller.h"
 #import "chrome/browser/cocoa/url_drop_target.h"
+#import "chrome/browser/cocoa/view_id_util.h"
 
 @implementation AutocompleteTextField
 
 @synthesize observer = observer_;
 
 + (Class)cellClass {
   return [AutocompleteTextFieldCell class];
 }
 
 - (void)dealloc {
@@ skipping 358 matching lines @@
 // (URLDropTarget protocol)
 - (BOOL)performDragOperation:(id<NSDraggingInfo>)sender {
   return [dropHandler_ performDragOperation:sender];
 }
 
 - (NSMenu*)decorationMenuForEvent:(NSEvent*)event {
   AutocompleteTextFieldCell* cell = [self cell];
   return [cell decorationMenuForEvent:event inRect:[self bounds] ofView:self];
 }
 
+- (ViewID)viewID {
+  return VIEW_ID_LOCATION_BAR;
+}
+
 @end