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 269781)
+++ chrome/browser/prerender/prerender_contents.cc	(working copy)
@@ -39,8 +39,10 @@
 #include "content/public/browser/web_contents_delegate.h"
 #include "content/public/common/frame_navigate_params.h"
 #include "content/public/common/page_transition_types.h"
+#include "net/url_request/url_request_context_getter.h"
 #include "ui/gfx/rect.h"
 
+using content::BrowserThread;
 using content::DownloadItem;
 using content::OpenURLParams;
 using content::RenderViewHost;
@@ -291,7 +293,8 @@
 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_);
@@ -339,6 +342,24 @@
   // the event of a mismatch.
   alias_session_storage_namespace->AddTransactionLogProcessId(child_id_);
 
+  // Add the RenderProcessHost to the Prerender Manager.
+  prerender_manager()->AddPrerenderProcessHost(
+      GetRenderViewHost()->GetProcess());
+
+  // In the prerender tracker, 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.
+  BrowserThread::PostTask(
+      BrowserThread::IO, FROM_HERE,
+      base::Bind(&PrerenderTracker::AddPrerenderCookieStoreOnIOThread,
+                 base::Unretained(prerender_manager()->prerender_tracker()),
+                 GetRenderViewHost()->GetProcess()->GetID(),
+                 make_scoped_refptr(request_context),
+                 base::Bind(&PrerenderContents::Destroy,
+                            AsWeakPtr(),
+                            FINAL_STATUS_COOKIE_CONFLICT)));
+
   NotifyPrerenderStart();
 
   // Close ourselves when the application is shutting down.
@@ -796,8 +817,8 @@
 
   NotifyPrerenderStop();
 
-  content::BrowserThread::PostTask(
-      content::BrowserThread::IO,
+  BrowserThread::PostTask(
+      BrowserThread::IO,
       FROM_HERE,
       base::Bind(&ResumeThrottles, resource_throttles_));
   resource_throttles_.clear();