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

chrome/common/chrome_features.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 "chrome/common/chrome_features.h"
 
 namespace features {
 
 // All features in alphabetical order.
 
@@ skipping 40 matching lines @@
 // deprecated systems.
 const base::Feature kLinuxObsoleteSystemIsEndOfTheLine{
     "LinuxObsoleteSystemIsEndOfTheLine", base::FEATURE_DISABLED_BY_DEFAULT};
 #endif
 
 // Enables or disables the Material Design version of chrome://history.
 const base::Feature kMaterialDesignHistoryFeature {
   "MaterialDesignHistory", base::FEATURE_DISABLED_BY_DEFAULT
 };
 
+// Enables or disables the Material Design version of chrome://settings.
+// Also affects chrome://help.
+const base::Feature kMaterialDesignSettingsFeature{
+    "MaterialDesignSettings", base::FEATURE_DISABLED_BY_DEFAULT};
+
 #if defined(OS_CHROMEOS)
 // Runtime flag that indicates whether this leak detector should be enabled in
 // the current instance of Chrome.
 const base::Feature kRuntimeMemoryLeakDetector{
     "RuntimeMemoryLeakDetector", base::FEATURE_DISABLED_BY_DEFAULT};
 #endif  // defined(OS_CHROMEOS)
 
 const base::Feature kSafeSearchUrlReporting{"SafeSearchUrlReporting",
                                             base::FEATURE_DISABLED_BY_DEFAULT};
 
@@ skipping 10 matching lines @@
                                           base::FEATURE_DISABLED_BY_DEFAULT};
 #endif
 
 #if defined(OS_CHROMEOS)
 // Enables or disables the opt-in IME menu in the language settings page.
 const base::Feature kOptInImeMenu{"OptInImeMenu",
                                   base::FEATURE_DISABLED_BY_DEFAULT};
 #endif  // defined(OS_CHROMEOS)
 
 }  // namespace features