webui: Do not set 'toolkit' property for webui.

ui/webui/resources/js/cr.js

Index: ui/webui/resources/js/cr.js
diff --git a/ui/webui/resources/js/cr.js b/ui/webui/resources/js/cr.js
index bf1a7474f0f514074545a490158c5f2ad5cd91c2..ceb1eb9707474fb9d91f9bc6b12ad5b13858569f 100644
--- a/ui/webui/resources/js/cr.js
+++ b/ui/webui/resources/js/cr.js
@@ -431,11 +431,5 @@ var cr = function() {
     get isLinux() {
       return /Linux/.test(navigator.userAgent);
     },
-
-    /** Whether this uses the views toolkit or not. */
-    get isViews() {
-      return typeof chrome.getVariableValue == 'function' &&
-          /views/.test(chrome.getVariableValue('toolkit'));
-    },
   };
 }();