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

chrome/browser/prerender/prerender_final_status.cc

 // 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.
 
 #include "chrome/browser/prerender/prerender_final_status.h"
 
 #include "chrome/browser/prerender/prerender_manager.h"
 
 namespace prerender {
 
@@ skipping 29 matching lines @@
   "window.opener",
   "Page ID Conflict",
   "Safe Browsing",
   "Fragment Mismatch",
   "SSL Client Certificate Requested",
   "Cache or History Cleared",
   "Cancelled",
   "SSL Error",
   "Cross-Site Navigation Pending",
   "DevTools Attached To The Tab",
+  "Session Storage Namespace Mismatch",
   "Max",
 };
 COMPILE_ASSERT(arraysize(kFinalStatusNames) == FINAL_STATUS_MAX + 1,
                PrerenderFinalStatus_name_count_mismatch);
 
 }
 
 const char* NameFromFinalStatus(FinalStatus final_status) {
   DCHECK_LT(static_cast<unsigned int>(final_status),
             arraysize(kFinalStatusNames));
   return kFinalStatusNames[final_status];
 }
 
 }  // namespace prerender