DevTools: Get rid of Element.prototype.enableStyleClass

Source/devtools/front_end/ScriptFormatterEditorAction.js

 // Copyright 2014 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.
 
 /**
  * @constructor
  * @implements {WebInspector.SourceMapping}
  * @param {!WebInspector.Workspace} workspace
  * @param {!WebInspector.DebuggerModel} debuggerModel
  */
@@ skipping 271 matching lines @@
         if (wasSelected)
             this._updateButton(null);
         this._discardFormattedUISourceCodeScript(uiSourceCode);
     },
 
     /**
      * @param {?WebInspector.UISourceCode} uiSourceCode
      */
     _updateButton: function(uiSourceCode)
     {
-        this._button.element.enableStyleClass("hidden", !this._isFormatableScript(uiSourceCode));
+        this._button.element.classList.toggle("hidden", !this._isFormatableScript(uiSourceCode));
     },
 
     /**
      * @param {!WebInspector.SourcesPanel} panel
      * @return {!Element}
      */
     button: function(panel)
     {
         if (this._button)
             return this._button.element;
@@ skipping 69 matching lines @@
     },
 
     /**
      * @param {!WebInspector.UISourceCode} uiSourceCode
      */
     _discardFormattedUISourceCodeScript: function(uiSourceCode)
     {
         this._scriptMapping._discardFormattedUISourceCodeScript(uiSourceCode);
     }
 }