Prerendered tabs use the same SessionStorage namespace as the tab that triggered the prerender.

chrome/browser/prerender/prerender_contents.h

 // Copyright (c) 2011 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.
 
 #ifndef CHROME_BROWSER_PRERENDER_PRERENDER_CONTENTS_H_
 #define CHROME_BROWSER_PRERENDER_PRERENDER_CONTENTS_H_
 #pragma once
 
 #include <list>
 #include <string>
 #include <vector>
 
 #include "base/memory/scoped_ptr.h"
 #include "base/time.h"
 #include "base/values.h"
 #include "chrome/browser/prerender/prerender_final_status.h"
 #include "content/browser/tab_contents/tab_contents_observer.h"
 #include "content/public/browser/notification_registrar.h"
 
 class Profile;
 class RenderViewHost;
 class RenderViewHostDelegate;
+class SessionStorageNamespace;
 class TabContents;
 class TabContentsWrapper;
 struct FaviconURL;
 struct ViewHostMsg_FrameNavigate_Params;
 
 namespace base {
 class ProcessMetrics;
 }
 
 namespace gfx {
@@ skipping 46 matching lines @@
   };
   typedef std::list<PendingPrerenderData> PendingPrerenderList;
 
   virtual ~PrerenderContents();
 
   bool Init();
 
   static Factory* CreateFactory();
 
   // |source_render_view_host| is the RenderViewHost that initiated
-  // prerendering.  It must be non-NULL and have its own view.  It is used
-  // solely to determine the window bounds while prerendering.
-  virtual void StartPrerendering(const RenderViewHost* source_render_view_host);
+  // prerendering.
+  virtual void StartPrerendering(
+      const RenderViewHost* source_render_view_host,
+      SessionStorageNamespace* session_storage_namespace);
 
   // Verifies that the prerendering is not using too many resources, and kills
   // it if not.
   void DestroyWhenUsingTooManyResources();
 
   RenderViewHost* render_view_host_mutable();
   const RenderViewHost* render_view_host() const;
 
   ViewHostMsg_FrameNavigate_Params* navigate_params() {
     return navigate_params_.get();
@@ skipping 206 matching lines @@
 
   // Offset by which to offset prerendered pages
   static const int32 kPrerenderPageIdOffset = 10;
 
   DISALLOW_COPY_AND_ASSIGN(PrerenderContents);
 };
 
 }  // namespace prerender
 
 #endif  // CHROME_BROWSER_PRERENDER_PRERENDER_CONTENTS_H_