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

chrome/browser/ui/webui/uber/uber_ui_browsertest.cc

 // Copyright (c) 2015 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 <utility>
 
 #include "base/command_line.h"
 #include "base/feature_list.h"
 #include "base/macros.h"
 #include "chrome/browser/extensions/extension_service.h"
 #include "chrome/browser/extensions/test_extension_system.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/ui/browser.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/url_constants.h"
 #include "chrome/test/base/ui_test_utils.h"
 #include "chrome/test/base/web_ui_browser_test.h"
 #include "content/public/common/content_switches.h"
 #include "content/public/test/browser_test_utils.h"
 #include "extensions/browser/extension_registry.h"
 #include "extensions/common/extension.h"
 #include "extensions/common/extension_builder.h"
@@ skipping 66 matching lines @@
       features::kMaterialDesignExtensions.name, "");
   base::FeatureList::ClearInstanceForTesting();
   base::FeatureList::SetInstance(std::move(feature_list));
 
   ui_test_utils::NavigateToURL(browser(), GURL(chrome::kChromeUIUberFrameURL));
   SelectTab();
   EXPECT_TRUE(GetJsBool("$('extensions').hidden"));
 }
 
 IN_PROC_BROWSER_TEST_F(UberUIBrowserTest, EnableMdHistoryHidesHistory) {
-  std::unique_ptr<base::FeatureList> feature_list(new base::FeatureList);
-  feature_list->InitializeFromCommandLine(
-      features::kMaterialDesignHistory.name, "");
-  base::FeatureList::ClearInstanceForTesting();
-  base::FeatureList::SetInstance(std::move(feature_list));
+  MdHistoryUI::SetEnabledForTesting(true);
 
   ui_test_utils::NavigateToURL(browser(), GURL(chrome::kChromeUIUberFrameURL));
   SelectTab();
   EXPECT_TRUE(GetJsBool("$('history').hidden"));
 }
 
 IN_PROC_BROWSER_TEST_F(UberUIBrowserTest, EnableMdSettingsHidesSettings) {
   std::unique_ptr<base::FeatureList> feature_list(new base::FeatureList);
   feature_list->InitializeFromCommandLine(
       features::kMaterialDesignSettings.name, "");
   base::FeatureList::ClearInstanceForTesting();
   base::FeatureList::SetInstance(std::move(feature_list));
 
   ui_test_utils::NavigateToURL(browser(), GURL(chrome::kChromeUIUberFrameURL));
   SelectTab();
   EXPECT_TRUE(GetJsBool("$('settings').hidden && $('help').hidden"));
 }
 
 IN_PROC_BROWSER_TEST_F(UberUIBrowserTest,
                        EnableSettingsWindowHidesSettingsAndHelp) {
   base::CommandLine::ForCurrentProcess()->AppendSwitch(
       ::switches::kEnableSettingsWindow);
   ui_test_utils::NavigateToURL(browser(), GURL(chrome::kChromeUIUberFrameURL));
   SelectTab();
   EXPECT_TRUE(GetJsBool("$('settings').hidden && $('help').hidden"));
 }