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

content/browser/renderer_host/render_view_host.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 CONTENT_BROWSER_RENDERER_HOST_RENDER_VIEW_HOST_H_
 #define CONTENT_BROWSER_RENDERER_HOST_RENDER_VIEW_HOST_H_
 #pragma once
 
 #include <string>
 #include <vector>
@@ skipping 454 matching lines @@
   void DisassociateFromPopupCount();
 
   // Notification that a move or resize renderer's containing window has
   // started.
   void NotifyMoveOrResizeStarted();
 
   // Notifies the renderer that the user has closed the FindInPage window
   // (and what action to take regarding the selection).
   void StopFinding(const ViewMsg_StopFinding_Params& params);
 
+  SessionStorageNamespace* session_storage_namespace() {
+    return session_storage_namespace_.get();
+  }
+
   // NOTE: Do not add functions that just send an IPC message that are called in
   // one or two places.  Have the caller send the IPC message directly.
 
  protected:
   friend class RenderViewHostObserver;
 
   // Add and remove observers for filtering IPC messages.  Clients must be sure
   // to remove the observer before they go away.
   void AddObserver(RenderViewHostObserver* observer);
   void RemoveObserver(RenderViewHostObserver* observer);
@@ skipping 186 matching lines @@
   typedef std::map<int64, PowerSaveBlocker*> PowerSaveBlockerMap;
   PowerSaveBlockerMap power_save_blockers_;
 
   // A list of observers that filter messages.  Weak references.
   ObserverList<RenderViewHostObserver> observers_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderViewHost);
 };
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_RENDER_VIEW_HOST_H_