DevTools: move functionality away from ElementsPanel for better DOM tree control reuse.

third_party/WebKit/Source/devtools/front_end/ui/Toolbar.js

 /*
  * Copyright (C) 2009 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 927 matching lines @@
      * @param {string} location
      */
     _loadItems: function(location)
     {
         var extensions = self.runtime.extensions(WebInspector.ToolbarItem.Provider);
         var promises = [];
         for (var i = 0; i < extensions.length; ++i) {
             if (extensions[i].descriptor()["location"] === location)
                 promises.push(resolveItem(extensions[i]));
         }
-        this._promise = Promise.all(promises).then(appendItemsInOrder.bind(this));
+        Promise.all(promises).then(appendItemsInOrder.bind(this));
 
         /**
          * @param {!Runtime.Extension} extension
          * @return {!Promise.<?WebInspector.ToolbarItem>}
          */
         function resolveItem(extension)
         {
             var descriptor = extension.descriptor();
             if (descriptor["separator"])
                 return Promise.resolve(/** @type {?WebInspector.ToolbarItem} */(new WebInspector.ToolbarSeparator()));
@@ skipping 19 matching lines @@
         function appendItemsInOrder(items)
         {
             for (var i = 0; i < items.length; ++i) {
                 var item = items[i];
                 if (item)
                     this.appendToolbarItem(item);
             }
         }
     },
 
-    /**
-     * @return {!Promise}
-     */
-    onLoad: function()
-    {
-        return this._promise;
-    },
-
     __proto__: WebInspector.Toolbar.prototype
 }