Switch BookmarkTabHelper to use WebContentsUserData.

chrome/browser/tab_contents/web_drag_bookmark_handler_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/tab_contents/web_drag_bookmark_handler_mac.h"
 
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/browser_finder.h"
 #include "chrome/browser/ui/browser_window.h"
 #include "chrome/browser/ui/bookmarks/bookmark_tab_helper.h"
-#include "chrome/browser/ui/tab_contents/tab_contents.h"
 #include "content/public/browser/web_contents.h"
 
 using content::WebContents;
 
 WebDragBookmarkHandlerMac::WebDragBookmarkHandlerMac()
-    : tab_(NULL) {
+    : bookmark_tab_helper_(NULL),
+      web_contents_(NULL) {
 }
 
 WebDragBookmarkHandlerMac::~WebDragBookmarkHandlerMac() {}
 
 void WebDragBookmarkHandlerMac::DragInitialize(WebContents* contents) {
-  DCHECK(tab_ ? (tab_->web_contents() == contents) : true);
-  if (!tab_)
-    tab_ = TabContents::FromWebContents(contents);
+  web_contents_ = contents;
+  if (!bookmark_tab_helper_)
+    bookmark_tab_helper_ = BookmarkTabHelper::FromWebContents(contents);
 
   bookmark_drag_data_.ReadFromDragClipboard();
 }
 
 void WebDragBookmarkHandlerMac::OnDragOver() {
-  if (tab_ && tab_->bookmark_tab_helper()->GetBookmarkDragDelegate()) {
-    tab_->bookmark_tab_helper()->GetBookmarkDragDelegate()->OnDragOver(
+  if (bookmark_tab_helper_ && bookmark_tab_helper_->GetBookmarkDragDelegate()) {
+    bookmark_tab_helper_->GetBookmarkDragDelegate()->OnDragOver(
         bookmark_drag_data_);
   }
 }
 
 void WebDragBookmarkHandlerMac::OnDragEnter() {
-  if (tab_ && tab_->bookmark_tab_helper()->GetBookmarkDragDelegate()) {
-    tab_->bookmark_tab_helper()->GetBookmarkDragDelegate()->OnDragEnter(
+  if (bookmark_tab_helper_ && bookmark_tab_helper_->GetBookmarkDragDelegate()) {
+    bookmark_tab_helper_->GetBookmarkDragDelegate()->OnDragEnter(
         bookmark_drag_data_);
   }
 }
 
 void WebDragBookmarkHandlerMac::OnDrop() {
-  // This is non-null if tab_contents_ is showing an ExtensionWebUI with
+  // This is non-null if the web_contents_ is showing an ExtensionWebUI with
   // support for (at the moment experimental) drag and drop extensions.
-  if (tab_) {
-    if (tab_->bookmark_tab_helper()->GetBookmarkDragDelegate()) {
-      tab_->bookmark_tab_helper()->GetBookmarkDragDelegate()->OnDrop(
+  if (bookmark_tab_helper_) {
+    if (bookmark_tab_helper_->GetBookmarkDragDelegate()) {
+      bookmark_tab_helper_->GetBookmarkDragDelegate()->OnDrop(
           bookmark_drag_data_);
     }
 
     // Focus the target browser.
-    Browser* browser = browser::FindBrowserWithWebContents(
-        tab_->web_contents());
+    Browser* browser = browser::FindBrowserWithWebContents(web_contents_);
     if (browser)
       browser->window()->Show();
   }
 }
 
 void WebDragBookmarkHandlerMac::OnDragLeave() {
-  if (tab_ && tab_->bookmark_tab_helper()->GetBookmarkDragDelegate()) {
-    tab_->bookmark_tab_helper()->GetBookmarkDragDelegate()->OnDragLeave(
+  if (bookmark_tab_helper_ && bookmark_tab_helper_->GetBookmarkDragDelegate()) {
+    bookmark_tab_helper_->GetBookmarkDragDelegate()->OnDragLeave(
         bookmark_drag_data_);
   }
 }