MD History: truncate title to 300 chars in C++ instead of JS

chrome/browser/history/history_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 <utility>
 #include <vector>
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/files/file_path.h"
@@ skipping 278 matching lines @@
 
 // http://crbug.com/22111 (linux), http://crbug.com/530246 (win)
 #if defined(OS_LINUX) || defined(OS_WIN)
 #define MAYBE_HistorySearchXSS DISABLED_HistorySearchXSS
 #else
 #define MAYBE_HistorySearchXSS HistorySearchXSS
 #endif
 IN_PROC_BROWSER_TEST_F(HistoryBrowserTest, MAYBE_HistorySearchXSS) {
   // TODO(tsergeant): Enable this test on MD History once it is possible to pass
   // in a query via URL (crbug.com/619799).
-  MdHistoryUI::DisableForTesting();
+  MdHistoryUI::SetEnabledForTesting(false);
 
   GURL url(std::string(chrome::kChromeUIHistoryURL) +
       "#q=%3Cimg%20src%3Dx%3Ax%20onerror%3D%22document.title%3D'XSS'%22%3E");
   ui_test_utils::NavigateToURL(browser(), url);
   // Mainly, this is to ensure we send a synchronous message to the renderer
   // so that we're not susceptible (less susceptible?) to a race condition.
   // Should a race condition ever trigger, it won't result in flakiness.
   int num = ui_test_utils::FindInPage(
       browser()->tab_strip_model()->GetActiveWebContents(),
       base::ASCIIToUTF16("<img"), true,
@@ skipping 231 matching lines @@
 
   content::WebContents* active_web_contents =
       browser()->tab_strip_model()->GetActiveWebContents();
   ASSERT_EQ(web_contents, active_web_contents);
   ASSERT_EQ(history_url, active_web_contents->GetURL());
 
   content::WebContents* second_tab =
       browser()->tab_strip_model()->GetWebContentsAt(1);
   ASSERT_NE(history_url, second_tab->GetURL());
 }