[Mac]Implement ViewID support.

chrome/browser/tab_contents/tab_contents_view_mac.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 <Carbon/Carbon.h>
 
 #include "chrome/browser/tab_contents/tab_contents_view_mac.h"
 
 #include <string>
 
@@ skipping 312 matching lines @@
 
 @implementation TabContentsViewCocoa
 
 - (id)initWithTabContentsViewMac:(TabContentsViewMac*)w {
   self = [super initWithFrame:NSZeroRect];
   if (self != nil) {
     tabContentsView_ = w;
     dropTarget_.reset(
         [[WebDropTarget alloc] initWithTabContents:[self tabContents]]);
     [self registerDragTypes];
+    [self setViewID:VIEW_ID_TAB_CONTAINER];
   }
   return self;
 }
 
 - (void)dealloc {
   // Cancel any deferred tab closes, just in case.
   [self cancelDeferredClose];
 
   // This probably isn't strictly necessary, but can't hurt.
   [self unregisterDraggedTypes];
@@ skipping 115 matching lines @@
   [NSObject cancelPreviousPerformRequestsWithTarget:self
                                            selector:aSel
                                              object:nil];
 }
 
 - (void)closeTabAfterEvent {
   tabContentsView_->CloseTab();
 }
 
 @end