Modify prerendering to support having multiple session storage namespaces per tab.

chrome/browser/prerender/prerender_browsertest.cc

Index: chrome/browser/prerender/prerender_browsertest.cc
diff --git a/chrome/browser/prerender/prerender_browsertest.cc b/chrome/browser/prerender/prerender_browsertest.cc
index ec665307c3ef5903d36f22d402c54ad2c39a9ebb..c12ffdb6634262591d7e4bdba8ab0799592a1ef0 100644
--- a/chrome/browser/prerender/prerender_browsertest.cc
+++ b/chrome/browser/prerender/prerender_browsertest.cc
@@ -46,6 +46,7 @@
 #include "content/public/browser/devtools_manager.h"
 #include "content/public/browser/notification_service.h"
 #include "content/public/browser/render_view_host.h"
+#include "content/public/browser/session_storage_namespace.h"
 #include "content/public/browser/web_contents.h"
 #include "content/public/common/url_constants.h"
 #include "content/public/test/browser_test_utils.h"
@@ -58,6 +59,7 @@
 #include "ui/base/l10n/l10n_util.h"
 
 using content::BrowserThread;
+using content::SessionStorageNamespaceMap;
 using content::DevToolsAgentHost;
 using content::DevToolsAgentHostRegistry;
 using content::DevToolsClientHost;
@@ -246,9 +248,10 @@ class TestPrerenderContents : public PrerenderContents {
   }
 
   virtual WebContents* CreateWebContents(
-      content::SessionStorageNamespace* session_storage_namespace) OVERRIDE {
+      const SessionStorageNamespaceMap& session_storage_namespace_map)
+          OVERRIDE {
     WebContents* web_contents = PrerenderContents::CreateWebContents(
-        session_storage_namespace);
+        session_storage_namespace_map);
     string16 ready_title = ASCIIToUTF16(kReadyTitle);
     if (prerender_should_wait_for_ready_title_)
       ready_title_watcher_.reset(new content::TitleWatcher(
@@ -517,13 +520,13 @@ class PrerenderBrowserTest : virtual public InProcessBrowserTest {
 
   virtual ~PrerenderBrowserTest() {}
 
-  content::SessionStorageNamespace* GetSessionStorageNamespace() const {
+  const SessionStorageNamespaceMap& GetSessionStorageNamespaceMap() const {
     TabContents* tab_contents =
         current_browser()->tab_strip_model()->GetActiveTabContents();
     if (!tab_contents)
-      return NULL;
+      return kEmptyMap;
     return tab_contents->web_contents()->GetController()
-        .GetSessionStorageNamespaceMap().find("")->second;
+        .GetSessionStorageNamespaceMap();
   }
 
   virtual void SetUpInProcessBrowserTestFixture() OVERRIDE {
@@ -744,7 +747,7 @@ class PrerenderBrowserTest : virtual public InProcessBrowserTest {
 
   bool UrlIsInPrerenderManager(const GURL& url) const {
     return GetPrerenderManager()->FindPrerenderData(
-        url, GetSessionStorageNamespace()) != NULL;
+        url, GetSessionStorageNamespaceMap()) != NULL;
   }
 
   // This only checks to see if the URL is pending in our TestPrerenderContents.
@@ -806,7 +809,7 @@ class PrerenderBrowserTest : virtual public InProcessBrowserTest {
   TestPrerenderContents* GetPrerenderContents() const {
     PrerenderManager::PrerenderData* prerender_data =
         GetPrerenderManager()->FindPrerenderData(
-            dest_url_, GetSessionStorageNamespace());
+            dest_url_, GetSessionStorageNamespaceMap());
     return static_cast<TestPrerenderContents*>(
         prerender_data ? prerender_data->contents() : NULL);
   }
@@ -1035,6 +1038,7 @@ class PrerenderBrowserTest : virtual public InProcessBrowserTest {
   std::string loader_path_;
   std::string loader_query_and_fragment_;
   Browser* explicitly_set_browser_;
+  const SessionStorageNamespaceMap kEmptyMap;  // Used for an error return.
 };
 
 // Checks that a page is correctly prerendered in the case of a