[MD Settings] Add feature to enable md-settings by default.

chrome/browser/ui/webui/uber/uber_ui.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 "chrome/browser/ui/webui/uber/uber_ui.h"
 
 #include "base/stl_util.h"
 #include "build/build_config.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/ui/webui/chrome_web_ui_controller_factory.h"
@@ skipping 78 matching lines @@
 
   // TODO(jhawkins): Attempt to get rid of IDS_SHORT_PRODUCT_OS_NAME.
 #if defined(OS_CHROMEOS)
   source->AddLocalizedString("shortProductName", IDS_SHORT_PRODUCT_OS_NAME);
 #else
   source->AddLocalizedString("shortProductName", IDS_SHORT_PRODUCT_NAME);
 #endif  // defined(OS_CHROMEOS)
 
   source->AddBoolean("hideExtensions", ::switches::MdExtensionsEnabled());
   source->AddBoolean("hideSettingsAndHelp",
-                     ::switches::SettingsWindowEnabled());
+                     ::switches::SettingsWindowEnabled() ||
+                         base::FeatureList::IsEnabled(
+                             features::kMaterialDesignSettingsFeature));
   source->AddString("extensionsHost", chrome::kChromeUIExtensionsHost);
   source->AddLocalizedString("extensionsDisplayName",
                              IDS_MANAGE_EXTENSIONS_SETTING_WINDOWS_TITLE);
   source->AddString("helpHost", chrome::kChromeUIHelpHost);
   source->AddLocalizedString("helpDisplayName", IDS_ABOUT_TITLE);
   source->AddString("historyHost", chrome::kChromeUIHistoryHost);
   source->AddLocalizedString("historyDisplayName", IDS_HISTORY_TITLE);
   source->AddString("settingsHost", chrome::kChromeUISettingsHost);
   source->AddLocalizedString("settingsDisplayName", IDS_SETTINGS_TITLE);
   bool overrides_history =
@@ skipping 131 matching lines @@
   // opens the default history page if one is uninstalled or disabled.
   UpdateHistoryNavigation(web_ui());
 }
 
 void UberFrameUI::OnExtensionUnloaded(
     content::BrowserContext* browser_context,
     const extensions::Extension* extension,
     extensions::UnloadedExtensionInfo::Reason reason) {
   UpdateHistoryNavigation(web_ui());
 }