MD Settings: ... and we fixed all CHECK()-based URL crashes once and for all.

chrome/browser/ui/webui/chrome_web_ui_controller_factory.cc

Index: chrome/browser/ui/webui/chrome_web_ui_controller_factory.cc
diff --git a/chrome/browser/ui/webui/chrome_web_ui_controller_factory.cc b/chrome/browser/ui/webui/chrome_web_ui_controller_factory.cc
index e4ae4c29613f18799f9e8b9de04abde0ed596b88..e317f854b276d7f7b68c9528ea91d4c2af06dc61 100644
--- a/chrome/browser/ui/webui/chrome_web_ui_controller_factory.cc
+++ b/chrome/browser/ui/webui/chrome_web_ui_controller_factory.cc
@@ -256,6 +256,12 @@ WebUIController* NewWebUI<dom_distiller::DomDistillerUi>(WebUI* web_ui,
       web_ui, service, dom_distiller::kDomDistillerScheme);
 }
 
+template<>
+WebUIController* NewWebUI<settings::MdSettingsUI>(WebUI* web_ui,
+                                                  const GURL& url) {
+  return new settings::MdSettingsUI(web_ui, url);
+}
+
 #if defined(ENABLE_EXTENSIONS)
 // Only create ExtensionWebUI for URLs that are allowed extension bindings,
 // hosted by actual tabs.