Only commit cookie changes in prerenders after a prerender is shown

chrome/browser/prerender/prerender_contents.cc

Index: chrome/browser/prerender/prerender_contents.cc
===================================================================
--- chrome/browser/prerender/prerender_contents.cc	(revision 265252)
+++ chrome/browser/prerender/prerender_contents.cc	(working copy)
@@ -289,7 +289,8 @@
 void PrerenderContents::StartPrerendering(
     int creator_child_id,
     const gfx::Size& size,
-    SessionStorageNamespace* session_storage_namespace) {
+    SessionStorageNamespace* session_storage_namespace,
+    net::URLRequestContextGetter* request_context) {
   DCHECK(profile_ != NULL);
   DCHECK(!size.IsEmpty());
   DCHECK(!prerendering_has_started_);
@@ -337,6 +338,17 @@
   // the event of a mismatch.
   alias_session_storage_namespace->AddTransactionLogProcessId(child_id_);
 
+  // Add this prerender to the prerender tracker. This will create a
+  // Prerender Cookie Store to keep track of cookie changes performed by the
+  // prerender. Once the prerender is shown, the cookie changes will be
+  // committed to the actual cookie store, otherwise, they will be discarded.
+  prerender_manager()->prerender_tracker()->AddPrerender(
+      GetRenderViewHost()->GetProcess(),
+      request_context,
+      base::Bind(&PrerenderContents::Destroy,
+                 AsWeakPtr(),
+                 FINAL_STATUS_COOKIE_CONFLICT));
+
   NotifyPrerenderStart();
 
   // Close ourselves when the application is shutting down.