Invalidate the page state when restoring WebUIs

chrome/browser/sessions/better_session_restore_browsertest.cc

Index: chrome/browser/sessions/better_session_restore_browsertest.cc
diff --git a/chrome/browser/sessions/better_session_restore_browsertest.cc b/chrome/browser/sessions/better_session_restore_browsertest.cc
index 07a97238305435238b506669a9f3e159c4bc4cf2..1f8a39f6b2b2ed13dd3faf2482e31a356b02fc1e 100644
--- a/chrome/browser/sessions/better_session_restore_browsertest.cc
+++ b/chrome/browser/sessions/better_session_restore_browsertest.cc
@@ -13,6 +13,7 @@
 #include "base/macros.h"
 #include "base/path_service.h"
 #include "base/strings/utf_string_conversions.h"
+#include "base/test/scoped_feature_list.h"
 #include "build/build_config.h"
 #include "chrome/browser/background/background_mode_manager.h"
 #include "chrome/browser/browser_process.h"
@@ -34,6 +35,8 @@
 #include "chrome/browser/ui/browser_window.h"
 #include "chrome/browser/ui/startup/startup_browser_creator.h"
 #include "chrome/browser/ui/tabs/tab_strip_model.h"
+#include "chrome/browser/ui/webui/md_history_ui.h"
+#include "chrome/common/chrome_features.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/pref_names.h"
 #include "chrome/common/url_constants.h"
@@ -482,6 +485,28 @@ IN_PROC_BROWSER_TEST_F(ContinueWhereILeftOffTest, SessionCookiesBrowserClose) {
   CheckReloadedPageRestored(new_browser);
 }
 
+// Test that switching MD History on behaves correctly with session restore.
+IN_PROC_BROWSER_TEST_F(ContinueWhereILeftOffTest, MDHistoryUpgrade) {

[sky, 2016/09/21 16:11:16]

Do you really need a browser test for this? Can't you write a unit test that
that verifies this?

[calamity, 2016/09/22 01:43:25]

I can verify that the page state is reset for WebUIs in a unit test, but I
really want to verify that session restore works correctly when the URL
switches. Session restore and page state stuff is pretty complex so I'm not sure
how I'd test this in a unit test.

[sky, 2016/09/22 13:21:37]

Verifying session restore is triggered on a title change seems separate from
your patch. I agree that is worth checking, but isn't really part of this patch.

[Dan Beam, 2016/09/22 18:09:20]

hey Scott,

I think Chris is just checking that the correct page loaded.  Both new and old
version of the History UI live on chrome://history and have the title "History".
 Chris added a global flag that changes the new UI's title to "MD History" so we
can tell the difference.

I believe it's all just to tell that the page actually loaded.

Right now (before this patch), when you have a chrome://history page open and
restart Chrome (and trigger session restore), the chrome://history tab is just
broken (like an Error page).

-- Dan

+  MdHistoryUI::use_test_title_ = true;
+  {
+    base::test::ScopedFeatureList feature_list;
+    feature_list.InitAndDisableFeature(features::kMaterialDesignHistory);
+    content::WebContents* web_contents =
+        browser()->tab_strip_model()->GetActiveWebContents();
+    content::TitleWatcher title_watcher(web_contents,
+                                        base::ASCIIToUTF16("History"));
+    ui_test_utils::NavigateToURL(browser(), GURL("chrome://history"));
+    base::string16 final_title = title_watcher.WaitAndGetTitle();
+  }
+  {
+    base::test::ScopedFeatureList feature_list;
+    feature_list.InitAndEnableFeature(features::kMaterialDesignHistory);
+    Browser* new_browser = QuitBrowserAndRestore(browser(), false);
+    // The new history page should have loaded.
+    CheckTitle(new_browser, base::ASCIIToUTF16("MD History"));
+  }
+}
+
 // Test that leaving a popup open will not prevent session restore.
 IN_PROC_BROWSER_TEST_F(ContinueWhereILeftOffTest,
                        SessionCookiesBrowserCloseWithPopupOpen) {