DevTools: migrate TabbedPane chevron over to UI.Icon.

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

 /*
  * Copyright (C) 2010 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 517 matching lines @@
   /**
    * @param {!UI.TabbedPaneTab} tab
    */
   _hideTabElement(tab) {
     this._tabsElement.removeChild(tab.tabElement);
     tab._shown = false;
   }
 
   _createDropDownButton() {
     var dropDownContainer = createElementWithClass('div', 'tabbed-pane-header-tabs-drop-down-container');
-    dropDownContainer.createChild('div', 'glyph');
+    var chevronIcon = UI.Icon.create('largeicon-chevron', 'chevron-icon');
+    dropDownContainer.appendChild(chevronIcon);
     this._dropDownMenu = new UI.DropDownMenu(dropDownContainer);
     this._dropDownMenu.addEventListener(UI.DropDownMenu.Events.ItemSelected, this._dropDownMenuItemSelected, this);
 
     return dropDownContainer;
   }
 
   /**
    * @param {!Common.Event} event
    */
   _dropDownMenuItemSelected(event) {
@@ skipping 666 matching lines @@
    * @param {!Array.<string>} ids
    */
   closeTabs(tabbedPane, ids) {},
 
   /**
    * @param {string} tabId
    * @param {!UI.ContextMenu} contextMenu
    */
   onContextMenu(tabId, contextMenu) {}
 };