Prerendered pages are swapped in at browser::Navigate time.

content/browser/tab_contents/tab_contents.h

Index: content/browser/tab_contents/tab_contents.h
diff --git a/content/browser/tab_contents/tab_contents.h b/content/browser/tab_contents/tab_contents.h
index 3e2bfa2c4d7f7ceff6fb2f98c6eb24d0219365fa..2beaaaea2ef3436b5a63d461757b462074e100bf 100644
--- a/content/browser/tab_contents/tab_contents.h
+++ b/content/browser/tab_contents/tab_contents.h
@@ -113,6 +113,10 @@ class CONTENT_EXPORT TabContents
     opener_web_ui_type_ = opener_web_ui_type;
   }
 
+  void set_opener_origin(const GURL& opener_origin) {
+    opener_origin_ = opener_origin;
+  }
+
   JavaBridgeDispatcherHostManager* java_bridge_dispatcher_host_manager() const {
     return java_bridge_dispatcher_host_manager_.get();
   }
@@ -215,6 +219,7 @@ class CONTENT_EXPORT TabContents
   virtual content::WebUI::TypeID GetWebUITypeForCurrentState() OVERRIDE;
   virtual content::WebUI* GetWebUIForCurrentState() OVERRIDE;
   virtual bool GotResponseToLockMouseRequest(bool allowed) OVERRIDE;
+  virtual const GURL& GetOpenerOrigin() const OVERRIDE;
 
   // Implementation of PageNavigator.
   virtual content::WebContents* OpenURL(
@@ -650,6 +655,9 @@ class CONTENT_EXPORT TabContents
   // Our view type. Default is VIEW_TYPE_TAB_CONTENTS.
   content::ViewType view_type_;
 
+  // The origin of the opener.
+  GURL opener_origin_;
+
   DISALLOW_COPY_AND_ASSIGN(TabContents);
 };