[DevTools] Migrate RequestHeadersView to TreeOutlineInShadow.

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

 /*
  * Copyright (C) 2007 Apple 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 324 matching lines @@
     registerRequiredCSS: function(cssFile)
     {
         WebInspector.appendStyle(this._shadowRoot, cssFile);
     },
 
     hideOverflow: function()
     {
         this._disclosureElement.classList.add("tree-outline-disclosure-hide-overflow");
     },
 
+    makeDense: function()
+    {
+        this.contentElement.classList.add("tree-outline-dense");
+    },
+
     __proto__: TreeOutline.prototype
 }
 
 /**
  * @constructor
  * @param {(string|!Node)=} title
  * @param {boolean=} expandable
  */
 function TreeElement(title, expandable)
 {
@@ skipping 809 matching lines @@
     isEventWithinDisclosureTriangle: function(event)
     {
         // FIXME: We should not use getComputedStyle(). For that we need to get rid of using ::before for disclosure triangle. (http://webk.it/74446)
         var paddingLeftValue = window.getComputedStyle(this._listItemNode).paddingLeft;
         console.assert(paddingLeftValue.endsWith("px"));
         var computedLeftPadding = parseFloat(paddingLeftValue);
         var left = this._listItemNode.totalOffsetLeft() + computedLeftPadding;
         return event.pageX >= left && event.pageX <= left + TreeElement._ArrowToggleWidth && this._expandable;
     }
 }