DevTools: reformat front-end code to match chromium style.

third_party/WebKit/Source/devtools/front_end/timeline_model/TimelineProfileTree.js

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
-
-WebInspector.TimelineProfileTree = { };
+WebInspector.TimelineProfileTree = {};
 
 /**
- * @constructor
+ * @unrestricted
  */
-WebInspector.TimelineProfileTree.Node = function()
-{
+WebInspector.TimelineProfileTree.Node = class {
+  constructor() {
     /** @type {number} */
     this.totalTime;
     /** @type {number} */
     this.selfTime;
     /** @type {string} */
     this.id;
     /** @type {!WebInspector.TracingModel.Event} */
     this.event;
     /** @type {?Map<string|symbol,!WebInspector.TimelineProfileTree.Node>} */
     this.children;
     /** @type {?WebInspector.TimelineProfileTree.Node} */
     this.parent;
     this._isGroupNode = false;
-};
+  }
 
-WebInspector.TimelineProfileTree.Node.prototype = {
-    /**
-     * @return {boolean}
-     */
-    isGroupNode: function()
-    {
-        return this._isGroupNode;
-    }
+  /**
+   * @return {boolean}
+   */
+  isGroupNode() {
+    return this._isGroupNode;
+  }
 };
 
 /**
  * @param {!Array<!WebInspector.TracingModel.Event>} events
  * @param {!Array<!WebInspector.TimelineModel.Filter>} filters
  * @param {number} startTime
  * @param {number} endTime
  * @param {function(!WebInspector.TracingModel.Event):(string|symbol)=} eventIdCallback
  * @return {!WebInspector.TimelineProfileTree.Node}
  */
-WebInspector.TimelineProfileTree.buildTopDown = function(events, filters, startTime, endTime, eventIdCallback)
-{
-    // Temporarily deposit a big enough value that exceeds the max recording time.
-    var /** @const */ initialTime = 1e7;
-    var root = new WebInspector.TimelineProfileTree.Node();
-    root.totalTime = initialTime;
-    root.selfTime = initialTime;
-    root.children = /** @type {!Map<string, !WebInspector.TimelineProfileTree.Node>} */ (new Map());
-    var parent = root;
+WebInspector.TimelineProfileTree.buildTopDown = function(events, filters, startTime, endTime, eventIdCallback) {
+  // Temporarily deposit a big enough value that exceeds the max recording time.
+  var /** @const */ initialTime = 1e7;
+  var root = new WebInspector.TimelineProfileTree.Node();
+  root.totalTime = initialTime;
+  root.selfTime = initialTime;
+  root.children = /** @type {!Map<string, !WebInspector.TimelineProfileTree.Node>} */ (new Map());
+  var parent = root;
 
-    /**
-     * @param {!WebInspector.TracingModel.Event} e
-     */
-    function onStartEvent(e)
-    {
-        if (!WebInspector.TimelineModel.isVisible(filters, e))
-            return;
-        var time = e.endTime ? Math.min(endTime, e.endTime) - Math.max(startTime, e.startTime) : 0;
-        var id = eventIdCallback ? eventIdCallback(e) : Symbol("uniqueEventId");
-        if (!parent.children)
-            parent.children = /** @type {!Map<string,!WebInspector.TimelineProfileTree.Node>} */ (new Map());
-        var node = parent.children.get(id);
-        if (node) {
-            node.selfTime += time;
-            node.totalTime += time;
-        } else {
-            node = new WebInspector.TimelineProfileTree.Node();
-            node.totalTime = time;
-            node.selfTime = time;
-            node.parent = parent;
-            node.id = id;
-            node.event = e;
-            parent.children.set(id, node);
-        }
-        parent.selfTime -= time;
-        if (parent.selfTime < 0) {
-            console.log("Error: Negative self of " + parent.selfTime, e);
-            parent.selfTime = 0;
-        }
-        if (e.endTime)
-            parent = node;
+  /**
+   * @param {!WebInspector.TracingModel.Event} e
+   */
+  function onStartEvent(e) {
+    if (!WebInspector.TimelineModel.isVisible(filters, e))
+      return;
+    var time = e.endTime ? Math.min(endTime, e.endTime) - Math.max(startTime, e.startTime) : 0;
+    var id = eventIdCallback ? eventIdCallback(e) : Symbol('uniqueEventId');
+    if (!parent.children)
+      parent.children = /** @type {!Map<string,!WebInspector.TimelineProfileTree.Node>} */ (new Map());
+    var node = parent.children.get(id);
+    if (node) {
+      node.selfTime += time;
+      node.totalTime += time;
+    } else {
+      node = new WebInspector.TimelineProfileTree.Node();
+      node.totalTime = time;
+      node.selfTime = time;
+      node.parent = parent;
+      node.id = id;
+      node.event = e;
+      parent.children.set(id, node);
     }
+    parent.selfTime -= time;
+    if (parent.selfTime < 0) {
+      console.log('Error: Negative self of ' + parent.selfTime, e);
+      parent.selfTime = 0;
+    }
+    if (e.endTime)
+      parent = node;
+  }
 
-    /**
-     * @param {!WebInspector.TracingModel.Event} e
-     */
-    function onEndEvent(e)
-    {
-        if (!WebInspector.TimelineModel.isVisible(filters, e))
-            return;
-        parent = parent.parent;
-    }
+  /**
+   * @param {!WebInspector.TracingModel.Event} e
+   */
+  function onEndEvent(e) {
+    if (!WebInspector.TimelineModel.isVisible(filters, e))
+      return;
+    parent = parent.parent;
+  }
 
-    var instantEventCallback = eventIdCallback ? undefined : onStartEvent; // Ignore instant events when aggregating.
-    WebInspector.TimelineModel.forEachEvent(events, onStartEvent, onEndEvent, instantEventCallback, startTime, endTime);
-    root.totalTime -= root.selfTime;
-    root.selfTime = 0;
-    return root;
+  var instantEventCallback = eventIdCallback ? undefined : onStartEvent;  // Ignore instant events when aggregating.
+  WebInspector.TimelineModel.forEachEvent(events, onStartEvent, onEndEvent, instantEventCallback, startTime, endTime);
+  root.totalTime -= root.selfTime;
+  root.selfTime = 0;
+  return root;
 };
 
 /**
  * @param {!WebInspector.TimelineProfileTree.Node} topDownTree
  * @param {?function(!WebInspector.TimelineProfileTree.Node):!WebInspector.TimelineProfileTree.Node=} groupingCallback
  * @return {!WebInspector.TimelineProfileTree.Node}
  */
-WebInspector.TimelineProfileTree.buildBottomUp = function(topDownTree, groupingCallback)
-{
-    var buRoot = new WebInspector.TimelineProfileTree.Node();
-    buRoot.selfTime = 0;
-    buRoot.totalTime = 0;
-    /** @type {!Map<string, !WebInspector.TimelineProfileTree.Node>} */
-    buRoot.children = new Map();
-    var nodesOnStack = /** @type {!Set<string>} */ (new Set());
-    if (topDownTree.children)
-        topDownTree.children.forEach(processNode);
-    buRoot.totalTime = topDownTree.totalTime;
-
-    /**
-     * @param {!WebInspector.TimelineProfileTree.Node} tdNode
-     */
-    function processNode(tdNode)
-    {
-        var buParent = groupingCallback && groupingCallback(tdNode) || buRoot;
-        if (buParent !== buRoot) {
-            buRoot.children.set(buParent.id, buParent);
-            buParent.parent = buRoot;
-        }
-        appendNode(tdNode, buParent);
-        var hadNode = nodesOnStack.has(tdNode.id);
-        if (!hadNode)
-            nodesOnStack.add(tdNode.id);
-        if (tdNode.children)
-            tdNode.children.forEach(processNode);
-        if (!hadNode)
-            nodesOnStack.delete(tdNode.id);
-    }
-
-    /**
-     * @param {!WebInspector.TimelineProfileTree.Node} tdNode
-     * @param {!WebInspector.TimelineProfileTree.Node} buParent
-     */
-    function appendNode(tdNode, buParent)
-    {
-        var selfTime = tdNode.selfTime;
-        var totalTime = tdNode.totalTime;
-        buParent.selfTime += selfTime;
-        buParent.totalTime += selfTime;
-        while (tdNode.parent) {
-            if (!buParent.children)
-                buParent.children = /** @type {!Map<string,!WebInspector.TimelineProfileTree.Node>} */ (new Map());
-            var id = tdNode.id;
-            var buNode = buParent.children.get(id);
-            if (!buNode) {
-                buNode = new WebInspector.TimelineProfileTree.Node();
-                buNode.selfTime = selfTime;
-                buNode.totalTime = totalTime;
-                buNode.event = tdNode.event;
-                buNode.id = id;
-                buNode.parent = buParent;
-                buParent.children.set(id, buNode);
-            } else {
-                buNode.selfTime += selfTime;
-                if (!nodesOnStack.has(id))
-                    buNode.totalTime += totalTime;
-            }
-            tdNode = tdNode.parent;
-            buParent = buNode;
-        }
-    }
-
-    // Purge zero self time nodes.
-    var rootChildren = buRoot.children;
-    for (var item of rootChildren.entries()) {
-        if (item[1].selfTime === 0)
-            rootChildren.delete(/** @type {string} */(item[0]));
-    }
-
-    return buRoot;
+WebInspector.TimelineProfileTree.buildBottomUp = function(topDownTree, groupingCallback) {
+  var buRoot = new WebInspector.TimelineProfileTree.Node();
+  buRoot.selfTime = 0;
+  buRoot.totalTime = 0;
+  /** @type {!Map<string, !WebInspector.TimelineProfileTree.Node>} */
+  buRoot.children = new Map();
+  var nodesOnStack = /** @type {!Set<string>} */ (new Set());
+  if (topDownTree.children)
+    topDownTree.children.forEach(processNode);
+  buRoot.totalTime = topDownTree.totalTime;
+
+  /**
+   * @param {!WebInspector.TimelineProfileTree.Node} tdNode
+   */
+  function processNode(tdNode) {
+    var buParent = groupingCallback && groupingCallback(tdNode) || buRoot;
+    if (buParent !== buRoot) {
+      buRoot.children.set(buParent.id, buParent);
+      buParent.parent = buRoot;
+    }
+    appendNode(tdNode, buParent);
+    var hadNode = nodesOnStack.has(tdNode.id);
+    if (!hadNode)
+      nodesOnStack.add(tdNode.id);
+    if (tdNode.children)
+      tdNode.children.forEach(processNode);
+    if (!hadNode)
+      nodesOnStack.delete(tdNode.id);
+  }
+
+  /**
+   * @param {!WebInspector.TimelineProfileTree.Node} tdNode
+   * @param {!WebInspector.TimelineProfileTree.Node} buParent
+   */
+  function appendNode(tdNode, buParent) {
+    var selfTime = tdNode.selfTime;
+    var totalTime = tdNode.totalTime;
+    buParent.selfTime += selfTime;
+    buParent.totalTime += selfTime;
+    while (tdNode.parent) {
+      if (!buParent.children)
+        buParent.children = /** @type {!Map<string,!WebInspector.TimelineProfileTree.Node>} */ (new Map());
+      var id = tdNode.id;
+      var buNode = buParent.children.get(id);
+      if (!buNode) {
+        buNode = new WebInspector.TimelineProfileTree.Node();
+        buNode.selfTime = selfTime;
+        buNode.totalTime = totalTime;
+        buNode.event = tdNode.event;
+        buNode.id = id;
+        buNode.parent = buParent;
+        buParent.children.set(id, buNode);
+      } else {
+        buNode.selfTime += selfTime;
+        if (!nodesOnStack.has(id))
+          buNode.totalTime += totalTime;
+      }
+      tdNode = tdNode.parent;
+      buParent = buNode;
+    }
+  }
+
+  // Purge zero self time nodes.
+  var rootChildren = buRoot.children;
+  for (var item of rootChildren.entries()) {
+    if (item[1].selfTime === 0)
+      rootChildren.delete(/** @type {string} */ (item[0]));
+  }
+
+  return buRoot;
 };
 
 /**
  * @param {!WebInspector.TracingModel.Event} event
  * @return {?string}
  */
-WebInspector.TimelineProfileTree.eventURL = function(event)
-{
-    var data = event.args["data"] || event.args["beginData"];
-    if (data && data["url"])
-        return data["url"];
-    var frame = WebInspector.TimelineProfileTree.eventStackFrame(event);
-    while (frame) {
-        var url = frame["url"];
-        if (url)
-            return url;
-        frame = frame.parent;
-    }
-    return null;
+WebInspector.TimelineProfileTree.eventURL = function(event) {
+  var data = event.args['data'] || event.args['beginData'];
+  if (data && data['url'])
+    return data['url'];
+  var frame = WebInspector.TimelineProfileTree.eventStackFrame(event);
+  while (frame) {
+    var url = frame['url'];
+    if (url)
+      return url;
+    frame = frame.parent;
+  }
+  return null;
 };
 
 /**
  * @param {!WebInspector.TracingModel.Event} event
  * @return {?RuntimeAgent.CallFrame}
  */
-WebInspector.TimelineProfileTree.eventStackFrame = function(event)
-{
-    if (event.name === WebInspector.TimelineModel.RecordType.JSFrame)
-        return /** @type {?RuntimeAgent.CallFrame} */ (event.args["data"] || null);
-    var topFrame = event.stackTrace && event.stackTrace[0];
-    if (topFrame)
-        return /** @type {!RuntimeAgent.CallFrame} */ (topFrame);
-    var initiator = event.initiator;
-    return /** @type {?RuntimeAgent.CallFrame} */ (initiator && initiator.stackTrace && initiator.stackTrace[0] || null);
-};
-
-/**
- * @constructor
- * @param {function(!WebInspector.TracingModel.Event):string} titleMapper
- * @param {function(!WebInspector.TracingModel.Event):string} categoryMapper
- */
-WebInspector.TimelineAggregator = function(titleMapper, categoryMapper)
-{
+WebInspector.TimelineProfileTree.eventStackFrame = function(event) {
+  if (event.name === WebInspector.TimelineModel.RecordType.JSFrame)
+    return /** @type {?RuntimeAgent.CallFrame} */ (event.args['data'] || null);
+  var topFrame = event.stackTrace && event.stackTrace[0];
+  if (topFrame)
+    return /** @type {!RuntimeAgent.CallFrame} */ (topFrame);
+  var initiator = event.initiator;
+  return /** @type {?RuntimeAgent.CallFrame} */ (initiator && initiator.stackTrace && initiator.stackTrace[0] || null);
+};
+
+/**
+ * @unrestricted
+ */
+WebInspector.TimelineAggregator = class {
+  /**
+   * @param {function(!WebInspector.TracingModel.Event):string} titleMapper
+   * @param {function(!WebInspector.TracingModel.Event):string} categoryMapper
+   */
+  constructor(titleMapper, categoryMapper) {
     this._titleMapper = titleMapper;
     this._categoryMapper = categoryMapper;
     /** @type {!Map<string, !WebInspector.TimelineProfileTree.Node>} */
     this._groupNodes = new Map();
+  }
+
+  /**
+   * @param {!WebInspector.TracingModel.Event} event
+   * @return {string}
+   */
+  static eventId(event) {
+    if (event.name === WebInspector.TimelineModel.RecordType.JSFrame) {
+      var data = event.args['data'];
+      return 'f:' + data['functionName'] + '@' + (data['scriptId'] || data['url'] || '');
+    }
+    return event.name + ':@' + WebInspector.TimelineProfileTree.eventURL(event);
+  }
+
+  /**
+   * @param {string} url
+   * @return {boolean}
+   */
+  static isExtensionInternalURL(url) {
+    return url.startsWith(WebInspector.TimelineAggregator._extensionInternalPrefix);
+  }
+
+  /**
+   * @param {!WebInspector.TimelineAggregator.GroupBy} groupBy
+   * @return {?function(!WebInspector.TimelineProfileTree.Node):!WebInspector.TimelineProfileTree.Node}
+   */
+  groupFunction(groupBy) {
+    var idMapper = this._nodeToGroupIdFunction(groupBy);
+    return idMapper && this._nodeToGroupNode.bind(this, idMapper);
+  }
+
+  /**
+   * @param {!WebInspector.TimelineProfileTree.Node} root
+   * @param {!WebInspector.TimelineAggregator.GroupBy} groupBy
+   * @return {!WebInspector.TimelineProfileTree.Node}
+   */
+  performGrouping(root, groupBy) {
+    var nodeMapper = this.groupFunction(groupBy);
+    if (!nodeMapper)
+      return root;
+    for (var node of root.children.values()) {
+      var groupNode = nodeMapper(node);
+      groupNode.parent = root;
+      groupNode.selfTime += node.selfTime;
+      groupNode.totalTime += node.totalTime;
+      groupNode.children.set(node.id, node);
+      node.parent = root;
+    }
+    root.children = this._groupNodes;
+    return root;
+  }
+
+  /**
+   * @param {!WebInspector.TimelineAggregator.GroupBy} groupBy
+   * @return {?function(!WebInspector.TimelineProfileTree.Node):string}
+   */
+  _nodeToGroupIdFunction(groupBy) {
+    /**
+     * @param {!WebInspector.TimelineProfileTree.Node} node
+     * @return {string}
+     */
+    function groupByURL(node) {
+      return WebInspector.TimelineProfileTree.eventURL(node.event) || '';
+    }
+
+    /**
+     * @param {boolean} groupSubdomains
+     * @param {!WebInspector.TimelineProfileTree.Node} node
+     * @return {string}
+     */
+    function groupByDomain(groupSubdomains, node) {
+      var url = WebInspector.TimelineProfileTree.eventURL(node.event) || '';
+      if (WebInspector.TimelineAggregator.isExtensionInternalURL(url))
+        return WebInspector.TimelineAggregator._extensionInternalPrefix;
+      var parsedURL = url.asParsedURL();
+      if (!parsedURL)
+        return '';
+      if (parsedURL.scheme === 'chrome-extension')
+        return parsedURL.scheme + '://' + parsedURL.host;
+      if (!groupSubdomains)
+        return parsedURL.host;
+      if (/^[.0-9]+$/.test(parsedURL.host))
+        return parsedURL.host;
+      var domainMatch = /([^.]*\.)?[^.]*$/.exec(parsedURL.host);
+      return domainMatch && domainMatch[0] || '';
+    }
+
+    switch (groupBy) {
+      case WebInspector.TimelineAggregator.GroupBy.None:
+        return null;
+      case WebInspector.TimelineAggregator.GroupBy.EventName:
+        return node => node.event ? this._titleMapper(node.event) : '';
+      case WebInspector.TimelineAggregator.GroupBy.Category:
+        return node => node.event ? this._categoryMapper(node.event) : '';
+      case WebInspector.TimelineAggregator.GroupBy.Subdomain:
+        return groupByDomain.bind(null, false);
+      case WebInspector.TimelineAggregator.GroupBy.Domain:
+        return groupByDomain.bind(null, true);
+      case WebInspector.TimelineAggregator.GroupBy.URL:
+        return groupByURL;
+      default:
+        return null;
+    }
+  }
+
+  /**
+   * @param {string} id
+   * @param {!WebInspector.TracingModel.Event} event
+   * @return {!WebInspector.TimelineProfileTree.Node}
+   */
+  _buildGroupNode(id, event) {
+    var groupNode = new WebInspector.TimelineProfileTree.Node();
+    groupNode.id = id;
+    groupNode.selfTime = 0;
+    groupNode.totalTime = 0;
+    groupNode.children = new Map();
+    groupNode.event = event;
+    groupNode._isGroupNode = true;
+    this._groupNodes.set(id, groupNode);
+    return groupNode;
+  }
+
+  /**
+   * @param {function(!WebInspector.TimelineProfileTree.Node):string} nodeToGroupId
+   * @param {!WebInspector.TimelineProfileTree.Node} node
+   * @return {!WebInspector.TimelineProfileTree.Node}
+   */
+  _nodeToGroupNode(nodeToGroupId, node) {
+    var id = nodeToGroupId(node);
+    return this._groupNodes.get(id) || this._buildGroupNode(id, node.event);
+  }
 };
 
 /**
  * @enum {string}
  */
 WebInspector.TimelineAggregator.GroupBy = {
-    None: "None",
-    EventName: "EventName",
-    Category: "Category",
-    Domain: "Domain",
-    Subdomain: "Subdomain",
-    URL: "URL"
-};
-
-/**
- * @param {!WebInspector.TracingModel.Event} event
- * @return {string}
- */
-WebInspector.TimelineAggregator.eventId = function(event)
-{
-    if (event.name === WebInspector.TimelineModel.RecordType.JSFrame) {
-        var data = event.args["data"];
-        return "f:" + data["functionName"] + "@" + (data["scriptId"] || data["url"] || "");
-    }
-    return event.name + ":@" + WebInspector.TimelineProfileTree.eventURL(event);
-};
-
-WebInspector.TimelineAggregator._extensionInternalPrefix = "extensions::";
-WebInspector.TimelineAggregator._groupNodeFlag = Symbol("groupNode");
-
-/**
- * @param {string} url
- * @return {boolean}
- */
-WebInspector.TimelineAggregator.isExtensionInternalURL = function(url)
-{
-    return url.startsWith(WebInspector.TimelineAggregator._extensionInternalPrefix);
-};
-
-WebInspector.TimelineAggregator.prototype = {
-    /**
-     * @param {!WebInspector.TimelineAggregator.GroupBy} groupBy
-     * @return {?function(!WebInspector.TimelineProfileTree.Node):!WebInspector.TimelineProfileTree.Node}
-     */
-    groupFunction: function(groupBy)
-    {
-        var idMapper = this._nodeToGroupIdFunction(groupBy);
-        return idMapper && this._nodeToGroupNode.bind(this, idMapper);
-    },
-
-    /**
-     * @param {!WebInspector.TimelineProfileTree.Node} root
-     * @param {!WebInspector.TimelineAggregator.GroupBy} groupBy
-     * @return {!WebInspector.TimelineProfileTree.Node}
-     */
-    performGrouping: function(root, groupBy)
-    {
-        var nodeMapper = this.groupFunction(groupBy);
-        if (!nodeMapper)
-            return root;
-        for (var node of root.children.values()) {
-            var groupNode = nodeMapper(node);
-            groupNode.parent = root;
-            groupNode.selfTime += node.selfTime;
-            groupNode.totalTime += node.totalTime;
-            groupNode.children.set(node.id, node);
-            node.parent = root;
-        }
-        root.children = this._groupNodes;
-        return root;
-    },
-
-    /**
-     * @param {!WebInspector.TimelineAggregator.GroupBy} groupBy
-     * @return {?function(!WebInspector.TimelineProfileTree.Node):string}
-     */
-    _nodeToGroupIdFunction: function(groupBy)
-    {
-        /**
-         * @param {!WebInspector.TimelineProfileTree.Node} node
-         * @return {string}
-         */
-        function groupByURL(node)
-        {
-            return WebInspector.TimelineProfileTree.eventURL(node.event) || "";
-        }
-
-        /**
-         * @param {boolean} groupSubdomains
-         * @param {!WebInspector.TimelineProfileTree.Node} node
-         * @return {string}
-         */
-        function groupByDomain(groupSubdomains, node)
-        {
-            var url = WebInspector.TimelineProfileTree.eventURL(node.event) || "";
-            if (WebInspector.TimelineAggregator.isExtensionInternalURL(url))
-                return WebInspector.TimelineAggregator._extensionInternalPrefix;
-            var parsedURL = url.asParsedURL();
-            if (!parsedURL)
-                return "";
-            if (parsedURL.scheme === "chrome-extension")
-                return parsedURL.scheme + "://" + parsedURL.host;
-            if (!groupSubdomains)
-                return parsedURL.host;
-            if (/^[.0-9]+$/.test(parsedURL.host))
-                return parsedURL.host;
-            var domainMatch = /([^.]*\.)?[^.]*$/.exec(parsedURL.host);
-            return domainMatch && domainMatch[0] || "";
-        }
-
-        switch (groupBy) {
-        case WebInspector.TimelineAggregator.GroupBy.None: return null;
-        case WebInspector.TimelineAggregator.GroupBy.EventName: return node => node.event ? this._titleMapper(node.event) : "";
-        case WebInspector.TimelineAggregator.GroupBy.Category: return node => node.event ? this._categoryMapper(node.event) : "";
-        case WebInspector.TimelineAggregator.GroupBy.Subdomain: return groupByDomain.bind(null, false);
-        case WebInspector.TimelineAggregator.GroupBy.Domain: return groupByDomain.bind(null, true);
-        case WebInspector.TimelineAggregator.GroupBy.URL: return groupByURL;
-        default: return null;
-        }
-    },
-
-    /**
-     * @param {string} id
-     * @param {!WebInspector.TracingModel.Event} event
-     * @return {!WebInspector.TimelineProfileTree.Node}
-     */
-    _buildGroupNode: function(id, event)
-    {
-        var groupNode = new WebInspector.TimelineProfileTree.Node();
-        groupNode.id = id;
-        groupNode.selfTime = 0;
-        groupNode.totalTime = 0;
-        groupNode.children = new Map();
-        groupNode.event = event;
-        groupNode._isGroupNode = true;
-        this._groupNodes.set(id, groupNode);
-        return groupNode;
-    },
-
-    /**
-     * @param {function(!WebInspector.TimelineProfileTree.Node):string} nodeToGroupId
-     * @param {!WebInspector.TimelineProfileTree.Node} node
-     * @return {!WebInspector.TimelineProfileTree.Node}
-     */
-    _nodeToGroupNode: function(nodeToGroupId, node)
-    {
-        var id = nodeToGroupId(node);
-        return this._groupNodes.get(id) || this._buildGroupNode(id, node.event);
-    },
-};
+  None: 'None',
+  EventName: 'EventName',
+  Category: 'Category',
+  Domain: 'Domain',
+  Subdomain: 'Subdomain',
+  URL: 'URL'
+};
+
+
+WebInspector.TimelineAggregator._extensionInternalPrefix = 'extensions::';
+WebInspector.TimelineAggregator._groupNodeFlag = Symbol('groupNode');
+
+