[DevTools] Replace usages of document with custom functions.

Source/devtools/front_end/sources/Placard.js

 /*
  * Copyright (C) 2008 Apple Inc. All Rights Reserved.
  * Copyright (C) 2013 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:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 13 matching lines @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 /**
  * @constructor
  * @param {string} title
  * @param {string} subtitle
  */
 WebInspector.Placard = function(title, subtitle)
 {
-    this.element = document.createElementWithClass("div", "placard");
+    this.element = createElementWithClass("div", "placard");
     this.element.placard = this;
 
     this.subtitleElement = this.element.createChild("div", "subtitle");
     this.titleElement = this.element.createChild("div", "title");
 
     this._hidden = false;
     this.title = title;
     this.subtitle = subtitle;
     this.selected = false;
 }
@@ skipping 78 matching lines @@
         if (this._hidden === x)
             return;
         this._hidden = x;
         this.element.classList.toggle("hidden", x);
     },
 
     discard: function()
     {
     }
 }