DevTools: Remove unused variables. Disallow unused variables with eslint

third_party/WebKit/Source/devtools/front_end/workspace/UISourceCode.js

 /*
  * Copyright (C) 2011 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 155 matching lines @@
   remove() {
     this._project.deleteFile(this.url());
   }
 
   /**
    * @param {string} name
    * @param {string} url
    * @param {!Common.ResourceType=} contentType
    */
   _updateName(name, url, contentType) {
-    var oldURL = this.url();
     this._url = this._url.substring(0, this._url.length - this._name.length) + name;
     this._name = name;
     if (url)
       this._url = url;
     if (contentType)
       this._contentType = contentType;
     this.dispatchEventToListeners(Workspace.UISourceCode.Events.TitleChanged, this);
   }
 
   /**
@@ skipping 753 matching lines @@
 Workspace.UISourceCodeMetadata = class {
   /**
    * @param {?Date} modificationTime
    * @param {?number} contentSize
    */
   constructor(modificationTime, contentSize) {
     this.modificationTime = modificationTime;
     this.contentSize = contentSize;
   }
 };