Switch MetroPinTabHelper to use WebContentsUserData.

chrome/browser/ui/tab_contents/tab_contents.h

Index: chrome/browser/ui/tab_contents/tab_contents.h
diff --git a/chrome/browser/ui/tab_contents/tab_contents.h b/chrome/browser/ui/tab_contents/tab_contents.h
index 59a4a659636eee4519a610ec0ee9144451fbb45b..4c5b5a0f0a68c85b289a3b65e8c1aaf09446bbe9 100644
--- a/chrome/browser/ui/tab_contents/tab_contents.h
+++ b/chrome/browser/ui/tab_contents/tab_contents.h
@@ -39,7 +39,6 @@ class HungPluginTabHelper;
 class InfoBarControllerContentsCreator;
 class InfoBarTabHelper;
 class InstantLoader;
-class MetroPinTabHelper;
 class NavigationMetricsRecorder;
 class OffscreenTabContentsCreator;
 class OldBasePanelBrowserTest;
@@ -256,10 +255,6 @@ class TabContents : public content::WebContentsObserver {
   }
   InfoBarTabHelper* infobar_tab_helper() { return infobar_tab_helper_.get(); }
 
-  MetroPinTabHelper* metro_pin_tab_helper() {
-    return metro_pin_tab_helper_.get();
-  }
-
 #if defined(ENABLE_ONE_CLICK_SIGNIN)
   OneClickSigninHelper* one_click_signin_helper() {
     return one_click_signin_helper_.get();
@@ -366,7 +361,6 @@ class TabContents : public content::WebContentsObserver {
   scoped_ptr<HistoryTabHelper> history_tab_helper_;
   scoped_ptr<HungPluginTabHelper> hung_plugin_tab_helper_;
   scoped_ptr<InfoBarTabHelper> infobar_tab_helper_;
-  scoped_ptr<MetroPinTabHelper> metro_pin_tab_helper_;
 
   // PasswordManager and its delegate. The delegate must outlive the manager,
   // per documentation in password_manager.h.