MD Settings: Redirect chrome://chrome to MD About when MD Settings is on

chrome/browser/browser_about_handler.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/browser_about_handler.h"
 
 #include <string>
 
 #include "base/bind.h"
 #include "base/location.h"
@@ skipping 110 matching lines @@
       host = chrome::kChromeUISettingsHost;
       path = chrome::kChromeUIHelpHost;
     } else if (::switches::AboutInSettingsEnabled()) {
       host = chrome::kChromeUISettingsFrameHost;
       if (url->path().empty() || url->path() == "/")
         path = chrome::kChromeUIHelpHost;
     } else {
       host = chrome::kChromeUIUberHost;
       path = chrome::kChromeUIHelpHost + url->path();
     }
+  // Redirect chrome://chrome to chrome://settings/help, only for MD settings.
+  } else if (host == chrome::kChromeUIUberHost &&
+             base::FeatureList::IsEnabled(features::kMaterialDesignSettings) &&
+             (url->path().empty() || url->path() == "/")) {
+    host = chrome::kChromeUISettingsHost;
+    path = chrome::kChromeUIHelpHost;
   }
 
   GURL::Replacements replacements;
   replacements.SetHostStr(host);
   if (!path.empty())
     replacements.SetPathStr(path);
   *url = url->ReplaceComponents(replacements);
 
   // Having re-written the URL, make the chrome: handler process it.
   return false;
 }
 
 bool HandleNonNavigationAboutURL(const GURL& url) {
   const std::string spec(url.spec());
 
   if (base::LowerCaseEqualsASCII(spec, chrome::kChromeUIRestartURL)) {
     // Call AttemptRestart after chrome::Navigate() completes to avoid access of
     // gtk objects after they are destroyed by BrowserWindowGtk::Close().
     base::ThreadTaskRunnerHandle::Get()->PostTask(
         FROM_HERE, base::Bind(&chrome::AttemptRestart));
     return true;
   } else if (base::LowerCaseEqualsASCII(spec, chrome::kChromeUIQuitURL)) {
     base::ThreadTaskRunnerHandle::Get()->PostTask(
         FROM_HERE, base::Bind(&chrome::AttemptExit));
     return true;
   }
 
   return false;
 }