Fix: Prerendering was confusing SessionService to not save sessionStorage.

chrome/browser/sessions/session_restore_browsertest.cc

 // Copyright (c) 2012 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 "base/command_line.h"
 #include "base/file_path.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/defaults.h"
 #include "chrome/browser/first_run/first_run.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/profiles/profile_manager.h"
 #include "chrome/browser/sessions/session_restore.h"
 #include "chrome/browser/sessions/session_service.h"
 #include "chrome/browser/sessions/session_service_factory.h"
 #include "chrome/browser/sessions/session_service_test_helper.h"
 #include "chrome/browser/sessions/session_types.h"
 #include "chrome/browser/sessions/session_types_test_helper.h"
 #include "chrome/browser/sessions/tab_restore_service.h"
 #include "chrome/browser/sessions/tab_restore_service_factory.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/browser_commands.h"
 #include "chrome/browser/ui/browser_list.h"
 #include "chrome/browser/ui/browser_tabstrip.h"
 #include "chrome/browser/ui/browser_window.h"
+#include "chrome/browser/ui/tab_contents/tab_contents.h"
 #include "chrome/browser/ui/tabs/tab_strip_model.h"
 #include "chrome/common/chrome_notification_types.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/url_constants.h"
 #include "chrome/test/base/in_process_browser_test.h"
 #include "chrome/test/base/ui_test_utils.h"
 #include "content/public/browser/navigation_controller.h"
 #include "content/public/browser/navigation_entry.h"
 #include "content/public/browser/notification_service.h"
 #include "content/public/browser/notification_types.h"
@@ skipping 809 matching lines @@
   ASSERT_EQ(1u, BrowserList::size());
   ASSERT_EQ(url1_, chrome::GetActiveWebContents(new_browser)->GetURL());
   content::NavigationController* new_controller =
       &chrome::GetActiveWebContents(new_browser)->GetController();
   ASSERT_TRUE(new_controller->GetDefaultSessionStorageNamespace());
   std::string restored_session_storage_persistent_id =
       new_controller->GetDefaultSessionStorageNamespace()->persistent_id();
   EXPECT_EQ(session_storage_persistent_id,
             restored_session_storage_persistent_id);
 }
+
+IN_PROC_BROWSER_TEST_F(SessionRestoreTest, SessionStorageAfterTabReplace) {
+  // Simulate what prerendering does: create a new TabContents with the same
+  // SessionStorageNamespace as an existing tab, then replace the tab with it.
+  {
+    content::NavigationController* controller =
+        &chrome::GetActiveWebContents(browser())->GetController();
+    ASSERT_TRUE(controller->GetDefaultSessionStorageNamespace());
+
+    content::SessionStorageNamespaceMap session_storage_namespace_map;
+    session_storage_namespace_map[""] =
+        controller->GetDefaultSessionStorageNamespace();
+    scoped_ptr<content::WebContents> web_contents(
+        content::WebContents::CreateWithSessionStorage(
+            browser()->profile(), NULL, MSG_ROUTING_NONE, NULL,
+            session_storage_namespace_map));
+
+    TabStripModel* tab_strip_model = browser()->tab_strip_model();

[Avi (use Gerrit), 2012/09/21 12:51:00]

Can you note that you don't need any of the helpers that a TabContents provides,
but are creating a TabContents only because that's what the tab strip model
requires? I will need to know that when I hit this file in the TabContents work.

[marja, 2012/09/21 13:15:02]

Done.

+    scoped_ptr<TabContents> old_tab_contents(
+        tab_strip_model->ReplaceTabContentsAt(
+            tab_strip_model->active_index(),
+            TabContents::Factory::CreateTabContents(web_contents.release())));
+    // Navigate with the new tab.
+    ui_test_utils::NavigateToURL(browser(), url2_);
+    // old_tab_contents goes out of scope.
+  }
+
+  // Check that the sessionStorage data is going to be persisted.
+  content::NavigationController* controller =
+      &chrome::GetActiveWebContents(browser())->GetController();
+  EXPECT_TRUE(
+      controller->GetDefaultSessionStorageNamespace()->should_persist());
+}