WebUI: DisallowJavascript only on Refresh and non-same-page navigations

chrome/browser/ui/webui/settings/md_settings_ui_browsertest.cc

 // Copyright 2016 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 <string>
 
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/browser_commands.h"
 #include "chrome/browser/ui/tabs/tab_strip_model.h"
 #include "chrome/common/url_constants.h"
@@ skipping 42 matching lines @@
 
   auto handlers = browser()->tab_strip_model()->GetActiveWebContents()
       ->GetWebUI()->GetHandlersForTesting();
 
   for (content::WebUIMessageHandler* handler : *handlers) {
     handler->AllowJavascriptForTesting();
     handler->DisallowJavascript();
     handler->AllowJavascriptForTesting();
   }
 }
+
+IN_PROC_BROWSER_TEST_F(MdSettingsUITest, InPageNavigations) {
+  NavigateToURL(browser(), GURL(chrome::kChromeUIMdSettingsURL));
+
+  auto handlers = browser()->tab_strip_model()->GetActiveWebContents()
+      ->GetWebUI()->GetHandlersForTesting();
+  for (content::WebUIMessageHandler* handler : *handlers) {

[Charlie Reis, 2016/06/25 00:02:19]

nit: No braces needed.  Same below.

[tommycli, 2016/06/25 00:12:17]

Done.

+    handler->AllowJavascriptForTesting();
+  }
+
+  // Push onto window.history. Back should now be an in-page navigation.
+  ASSERT_TRUE(content::ExecuteScript(
+      browser()->tab_strip_model()->GetActiveWebContents(),
+     "window.history.pushState({}, '', 'foo.html')"));
+  chrome::GoBack(browser(), CURRENT_TAB);

[Charlie Reis, 2016/06/25 00:02:19]

You might need to use WaitForLoadStop to avoid flakiness.

(Did the test fail without the fix?)

[tommycli, 2016/06/25 00:12:17]

I didn't detect any flakiness on my machine (the test failed without the fix),
but I might just have a fast machine. I added the wait.

+
+  for (content::WebUIMessageHandler* handler : *handlers) {
+    EXPECT_TRUE(handler->IsJavascriptAllowed());
+  }
+}