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

chrome/browser/prerender/prerender_contents.cc

Index: chrome/browser/prerender/prerender_contents.cc
diff --git a/chrome/browser/prerender/prerender_contents.cc b/chrome/browser/prerender/prerender_contents.cc
index b1a841429f91f2021f5d68c045fd09c2418ee971..eaafff234aa0cdb976446f3656065d535ae9c43f 100644
--- a/chrome/browser/prerender/prerender_contents.cc
+++ b/chrome/browser/prerender/prerender_contents.cc
@@ -24,6 +24,7 @@
 #include "chrome/common/icon_messages.h"
 #include "chrome/common/render_messages.h"
 #include "chrome/common/url_constants.h"
+#include "content/browser/in_process_webkit/session_storage_namespace.h"
 #include "content/browser/renderer_host/render_view_host.h"
 #include "content/browser/renderer_host/resource_request_details.h"
 #include "content/browser/tab_contents/tab_contents_delegate.h"
@@ -63,9 +64,11 @@ class PrerenderContentsFactoryImpl : public PrerenderContents::Factory {
  public:
   virtual PrerenderContents* CreatePrerenderContents(
       PrerenderManager* prerender_manager, PrerenderTracker* prerender_tracker,
-      Profile* profile, const GURL& url, const GURL& referrer,
+      SessionStorageNamespace* session_storage_namespace, Profile* profile,
+      const GURL& url, const GURL& referrer,
       Origin origin, uint8 experiment_id) OVERRIDE {
-    return new PrerenderContents(prerender_manager, prerender_tracker, profile,
+    return new PrerenderContents(prerender_manager, prerender_tracker,
+                                 session_storage_namespace, profile,
                                  url, referrer, origin, experiment_id);
   }
 };
@@ -170,19 +173,23 @@ void PrerenderContents::StartPendingPrerenders() {
     prerender_manager_->AddPrerender(it->origin,
                                      std::make_pair(child_id_, route_id_),
                                      it->url,
-                                     it->referrer);
+                                     it->referrer,
+                                     NULL);

[cbentzel, 2011/10/26 21:48:29]

Note: This works because AddPrerender will rediscover the
SessionStorageNamespace using child_id_ and route_id_. It also may be better to
pass in directly.

   }
 }
 
-PrerenderContents::PrerenderContents(PrerenderManager* prerender_manager,
-                                     PrerenderTracker* prerender_tracker,
-                                     Profile* profile,
-                                     const GURL& url,
-                                     const GURL& referrer,
-                                     Origin origin,
-                                     uint8 experiment_id)
+PrerenderContents::PrerenderContents(
+  PrerenderManager* prerender_manager,
+  PrerenderTracker* prerender_tracker,
+  SessionStorageNamespace* session_storage_namespace,
+  Profile* profile,
+  const GURL& url,
+  const GURL& referrer,
+  Origin origin,
+  uint8 experiment_id)
     : prerender_manager_(prerender_manager),
       prerender_tracker_(prerender_tracker),
+      session_storage_namespace_(session_storage_namespace),
       prerender_url_(url),
       referrer_(referrer),
       profile_(profile),
@@ -216,7 +223,7 @@ void PrerenderContents::StartPrerendering(
 
   prerendering_has_started_ = true;
   TabContents* new_contents = new TabContents(profile_, NULL, MSG_ROUTING_NONE,
-                                              NULL, NULL);
+                                              NULL, session_storage_namespace_);
   prerender_contents_.reset(new TabContentsWrapper(new_contents));
   TabContentsObserver::Observe(new_contents);