Switch BookmarkTabHelper to use WebContentsUserData.

chrome/browser/bookmarks/bookmark_manager_extension_api.cc

Index: chrome/browser/bookmarks/bookmark_manager_extension_api.cc
diff --git a/chrome/browser/bookmarks/bookmark_manager_extension_api.cc b/chrome/browser/bookmarks/bookmark_manager_extension_api.cc
index 43e3b4d9dbd4ebf2dc43386561db261ea2bcff41..85f9b40a8e08f16a1a6f1aa3ffe2fb0735de0234 100644
--- a/chrome/browser/bookmarks/bookmark_manager_extension_api.cc
+++ b/chrome/browser/bookmarks/bookmark_manager_extension_api.cc
@@ -158,12 +158,16 @@ BookmarkManagerExtensionEventRouter::BookmarkManagerExtensionEventRouter(
     Profile* profile, TabContents* tab)
     : profile_(profile),
     tab_(tab) {
-  tab_->bookmark_tab_helper()->SetBookmarkDragDelegate(this);
+  BookmarkTabHelper* bookmark_tab_helper =
+      BookmarkTabHelper::FromWebContents(tab_->web_contents());
+  bookmark_tab_helper->SetBookmarkDragDelegate(this);
 }
 
 BookmarkManagerExtensionEventRouter::~BookmarkManagerExtensionEventRouter() {
-  if (tab_->bookmark_tab_helper()->GetBookmarkDragDelegate() == this)
-    tab_->bookmark_tab_helper()->SetBookmarkDragDelegate(NULL);
+  BookmarkTabHelper* bookmark_tab_helper =
+      BookmarkTabHelper::FromWebContents(tab_->web_contents());
+  if (bookmark_tab_helper->GetBookmarkDragDelegate() == this)
+    bookmark_tab_helper->SetBookmarkDragDelegate(NULL);
 }
 
 void BookmarkManagerExtensionEventRouter::DispatchEvent(