Source/WebInspectorUI/UserInterface/Views/OverviewTimelineView.js - WebKit - Git at Google

 /*
  * Copyright (C) 2013, 2015 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
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  *
  * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
  * THE POSSIBILITY OF SUCH DAMAGE.
  */

 WI.OverviewTimelineView = class OverviewTimelineView extends WI.TimelineView
 {
     constructor(recording, extraArguments)
     {
         console.assert(recording instanceof WI.TimelineRecording);

         super(recording, extraArguments);

         this._recording = recording;
         this._pendingRepresentedObjects = [];
         this._resourceDataGridNodeMap = new Map;

         if (WI.TimelineRecording.sourceCodeTimelinesSupported() && !this._recording.imported) {
             WI.settings.timelineOverviewGroupBySourceCode.addEventListener(WI.Setting.Event.Changed, this._handleGroupBySourceCodeSettingChanged, this);

             this._groupBySourceCodeNavigationItem = new WI.CheckboxNavigationItem("overview-timeline-group-by-resource", WI.UIString("Group By Resource"), WI.settings.timelineOverviewGroupBySourceCode.value);
             this._groupBySourceCodeNavigationItem.addEventListener(WI.CheckboxNavigationItem.Event.CheckedDidChange, this._handleGroupBySourceCodeNavigationItemCheckedDidChange, this);
         }

         let columns = {name: {}, source: {}, graph: {}};

         columns.name.title = WI.UIString("Name");
         columns.name.width = "20%";
         columns.name.icon = true;
         columns.name.locked = true;
         if (this._shouldGroupBySourceCode)
             columns.name.disclosure = true;

         columns.source.title = WI.UIString("Source");
         columns.source.width = "10%";
         columns.source.icon = true;
         columns.source.locked = true;
         if (this._shouldGroupBySourceCode)
             columns.source.hidden = true;

         this._timelineRuler = new WI.TimelineRuler;
         this._timelineRuler.allowsClippedLabels = true;

         columns.graph.width = "70%";
         columns.graph.headerView = this._timelineRuler;
         columns.graph.locked = true;

         this._dataGrid = new WI.TimelineDataGrid(columns);

         this.setupDataGrid(this._dataGrid);

         this._currentTimeMarker = new WI.TimelineMarker(0, WI.TimelineMarker.Type.CurrentTime);
         this._timelineRuler.addMarker(this._currentTimeMarker);

         this.element.classList.add("overview");
         this.addSubview(this._dataGrid);

         for (let timeline of this._relevantTimelines)
             timeline.addEventListener(WI.Timeline.Event.RecordAdded, this._handleTimelineRecordAdded, this);

         recording.addEventListener(WI.TimelineRecording.Event.SourceCodeTimelineAdded, this._sourceCodeTimelineAdded, this);
         recording.addEventListener(WI.TimelineRecording.Event.MarkerAdded, this._markerAdded, this);
         recording.addEventListener(WI.TimelineRecording.Event.Reset, this._recordingReset, this);

         this._loadExistingRecords();
     }

     // Public

     get secondsPerPixel()
     {
         return this._timelineRuler.secondsPerPixel;
     }

     set secondsPerPixel(x)
     {
         this._timelineRuler.secondsPerPixel = x;
     }

     attached()
     {
         super.attached();

         this._timelineRuler.needsLayout(WI.View.LayoutReason.Resize);
     }

     closed()
     {
         for (let timeline of this._recording.timelines.values())
             timeline.removeEventListener(WI.Timeline.Event.RecordAdded, this._handleTimelineRecordAdded, this);

         this._recording.removeEventListener(WI.TimelineRecording.Event.SourceCodeTimelineAdded, this._sourceCodeTimelineAdded, this);
         this._recording.removeEventListener(WI.TimelineRecording.Event.MarkerAdded, this._markerAdded, this);
         this._recording.removeEventListener(WI.TimelineRecording.Event.Reset, this._recordingReset, this);
     }

     get navigationItems()
     {
         let navigationItems = [];
         if (this._groupBySourceCodeNavigationItem)
             navigationItems.push(this._groupBySourceCodeNavigationItem);
         return navigationItems;
     }

     get selectionPathComponents()
     {
         let dataGridNode = this._dataGrid.selectedNode;
         if (!dataGridNode || dataGridNode.hidden)
             return null;

         let pathComponents = [];

         while (dataGridNode && !dataGridNode.root) {
             console.assert(dataGridNode instanceof WI.TimelineDataGridNode);
             if (dataGridNode.hidden)
                 return null;

             let pathComponent = new WI.TimelineDataGridNodePathComponent(dataGridNode);
             pathComponent.addEventListener(WI.HierarchicalPathComponent.Event.SiblingWasSelected, this.dataGridNodePathComponentSelected, this);
             pathComponents.unshift(pathComponent);
             dataGridNode = dataGridNode.parent;
         }

         return pathComponents;
     }

     reset()
     {
         super.reset();

         this._dataGrid.reset();

         this._pendingRepresentedObjects = [];
         this._resourceDataGridNodeMap.clear();
     }

     // Protected

     get showsImportedRecordingMessage()
     {
         return true;
     }

     dataGridNodePathComponentSelected(event)
     {
         let dataGridNode = event.data.pathComponent.timelineDataGridNode;
         console.assert(dataGridNode.dataGrid === this._dataGrid);

         dataGridNode.revealAndSelect();
     }

     layout()
     {
         let oldZeroTime = this._timelineRuler.zeroTime;
         let oldStartTime = this._timelineRuler.startTime;
         let oldEndTime = this._timelineRuler.endTime;
         let oldCurrentTime = this._currentTimeMarker.time;

         this._timelineRuler.zeroTime = this.zeroTime;
         this._timelineRuler.startTime = this.startTime;
         this._timelineRuler.endTime = this.endTime;
         this._currentTimeMarker.time = this.currentTime;

         // The TimelineDataGridNode graphs are positioned with percentages, so they auto resize with the view.
         // We only need to refresh the graphs when the any of the times change.
         if (this.zeroTime !== oldZeroTime || this.startTime !== oldStartTime || this.endTime !== oldEndTime || this.currentTime !== oldCurrentTime) {
             let dataGridNode = this._dataGrid.children[0];
             while (dataGridNode) {
                 dataGridNode.refreshGraph();
                 dataGridNode = dataGridNode.traverseNextNode(true, null, true);
             }
         }

         this._processPendingRepresentedObjects();
     }

     // Private

     get _relevantTimelines()
     {
         let timelines = [];
         for (let [type, timeline] of this._recording.timelines) {
             if (type === WI.TimelineRecord.Type.RenderingFrame || type === WI.TimelineRecord.Type.CPU || type === WI.TimelineRecord.Type.Memory)
                 continue;

             timelines.push(timeline);
         }
         return timelines;
     }

     get _shouldGroupBySourceCode()
     {
         // Always show imported records as non-grouped.
         if (this._recording.imported)
             return false;

         return WI.TimelineRecording.sourceCodeTimelinesSupported() && WI.settings.timelineOverviewGroupBySourceCode.value;
     }

     _loadExistingRecords()
     {
         this._pendingRepresentedObjects = [];
         this._resourceDataGridNodeMap.clear();

         this._dataGrid.removeChildren();

         if (this._shouldGroupBySourceCode) {
             let networkTimeline = this._recording.timelines.get(WI.TimelineRecord.Type.Network);
             if (networkTimeline)
                 this._pendingRepresentedObjects.pushAll(networkTimeline.records.map((record) => record.resource));

             this._pendingRepresentedObjects.pushAll(this._recording.sourceCodeTimelines);
         } else {
             for (let timeline of this._relevantTimelines)
                 this._pendingRepresentedObjects.pushAll(timeline.records);
         }

         this.needsLayout();
     }

     _compareDataGridNodesByStartTime(a, b)
     {
         function getStartTime(dataGridNode)
         {
             if (dataGridNode instanceof WI.ResourceTimelineDataGridNode)
                 return dataGridNode.resource.firstTimestamp;
             if (dataGridNode instanceof WI.SourceCodeTimelineTimelineDataGridNode)
                 return dataGridNode.sourceCodeTimeline.startTime;

             console.error("Unknown data grid node.", dataGridNode);
             return 0;
         }

         let result = getStartTime(a) - getStartTime(b);
         if (result)
             return result;

         // Fallback to comparing titles.
         return a.displayName().extendedLocaleCompare(b.displayName());
     }

     _insertDataGridNode(dataGridNode, parentDataGridNode)
     {
         console.assert(dataGridNode);
         console.assert(!dataGridNode.parent);

         if (!parentDataGridNode)
             parentDataGridNode = this._dataGrid;

         parentDataGridNode.insertChild(dataGridNode, insertionIndexForObjectInListSortedByFunction(dataGridNode, parentDataGridNode.children, this._compareDataGridNodesByStartTime));
     }

     _addResourceToDataGridIfNeeded(resource)
     {
         console.assert(resource);
         if (!resource)
             return null;

         // FIXME: replace with this._dataGrid.findDataGridNode(resource) once <https://webkit.org/b/155305> is fixed.
         let dataGridNode = this._resourceDataGridNodeMap.get(resource);
         if (!dataGridNode) {
             let resourceTimelineRecord = this._networkTimeline ? this._networkTimeline.recordForResource(resource) : null;
             if (!resourceTimelineRecord)
                 resourceTimelineRecord = new WI.ResourceTimelineRecord(resource);

             dataGridNode = new WI.ResourceTimelineDataGridNode(resourceTimelineRecord, {
                 graphDataSource: this,
                 includesGraph: true,
             });
             this._resourceDataGridNodeMap.set(resource, dataGridNode);
         }

         if (!dataGridNode.parent) {
             let parentFrame = resource.parentFrame;
             if (!parentFrame)
                 return null;

             let expandedByDefault = false;
             if (parentFrame.mainResource === resource || parentFrame.provisionalMainResource === resource) {
                 parentFrame = parentFrame.parentFrame;
                 expandedByDefault = !parentFrame; // Main frame expands by default.
             }

             if (expandedByDefault)
                 dataGridNode.expand();

             let parentDataGridNode = null;
             if (parentFrame) {
                 // Find the parent main resource, adding it if needed, to append this resource as a child.
                 let parentResource = parentFrame.provisionalMainResource || parentFrame.mainResource;

                 parentDataGridNode = this._addResourceToDataGridIfNeeded(parentResource);
                 console.assert(parentDataGridNode);
                 if (!parentDataGridNode)
                     return null;
             }

             this._insertDataGridNode(dataGridNode, parentDataGridNode);
         }

         dataGridNode.refresh();
         return dataGridNode;
     }

     _addSourceCodeTimeline(sourceCodeTimeline)
     {
         let dataGridNode = this._resourceDataGridNodeMap.get(sourceCodeTimeline);
         if (!dataGridNode) {
             dataGridNode = new WI.SourceCodeTimelineTimelineDataGridNode(sourceCodeTimeline, {
                 graphDataSource: this,
             });
             this._resourceDataGridNodeMap.set(sourceCodeTimeline, dataGridNode);
         }

         if (!dataGridNode.parent) {
             let parentDataGridNode = sourceCodeTimeline.sourceCodeLocation ? this._addResourceToDataGridIfNeeded(sourceCodeTimeline.sourceCode) : null;
             this._insertDataGridNode(dataGridNode, parentDataGridNode);
         }
     }

     _processPendingRepresentedObjects()
     {
         if (!this._pendingRepresentedObjects.length)
             return;

         for (var representedObject of this._pendingRepresentedObjects) {
             if (this._shouldGroupBySourceCode) {
                 if (representedObject instanceof WI.Resource)
                     this._addResourceToDataGridIfNeeded(representedObject);
                 else if (representedObject instanceof WI.SourceCodeTimeline)
                     this._addSourceCodeTimeline(representedObject);
                 else
                     console.error("Unknown represented object", representedObject);
             } else {
                 const options = {
                     graphDataSource: this,
                     shouldShowPopover: true,
                 };

                 let dataGridNode = null;
                 if (representedObject instanceof WI.ResourceTimelineRecord)
                     dataGridNode = new WI.ResourceTimelineDataGridNode(representedObject, options);
                 else if (representedObject instanceof WI.LayoutTimelineRecord)
                     dataGridNode = new WI.LayoutTimelineDataGridNode(representedObject, options);
                 else if (representedObject instanceof WI.MediaTimelineRecord)
                     dataGridNode = new WI.MediaTimelineDataGridNode(representedObject, options);
                 else if (representedObject instanceof WI.ScriptTimelineRecord)
                     dataGridNode = new WI.ScriptTimelineDataGridNode(representedObject, options);
                 else if (representedObject instanceof WI.HeapAllocationsTimelineRecord)
                     dataGridNode = new WI.HeapAllocationsTimelineDataGridNode(representedObject, options);

                 console.assert(dataGridNode, representedObject);
                 if (!dataGridNode)
                     continue;

                 let comparator = (a, b) => {
                     return a.record.startTime - b.record.startTime;
                 };

                 this._dataGrid.insertChild(dataGridNode, insertionIndexForObjectInListSortedByFunction(dataGridNode, this._dataGrid.children, comparator));
             }
         }

         this._pendingRepresentedObjects = [];
     }

     _handleGroupBySourceCodeSettingChanged(event)
     {
         let groupBySourceCode = this._shouldGroupBySourceCode;
         this._dataGrid.disclosureColumnIdentifier = groupBySourceCode ? "name" : undefined;
         this._dataGrid.setColumnVisible("source", !groupBySourceCode);
         if (this._groupBySourceCodeNavigationItem)
             this._groupBySourceCodeNavigationItem.checked = groupBySourceCode;

         this._loadExistingRecords();
     }

     _handleGroupBySourceCodeNavigationItemCheckedDidChange(event)
     {
         WI.settings.timelineOverviewGroupBySourceCode.value = !WI.settings.timelineOverviewGroupBySourceCode.value;
     }

     _handleTimelineRecordAdded(event)
     {
         let {record} = event.data;

         if (this._shouldGroupBySourceCode) {
             if (event.target.type !== WI.TimelineRecord.Type.Network)
                 return;

             console.assert(record instanceof WI.ResourceTimelineRecord);

             this._pendingRepresentedObjects.push(record.resource);
         } else
             this._pendingRepresentedObjects.push(record);

         this.needsLayout();
     }

     _sourceCodeTimelineAdded(event)
     {
         if (!this._shouldGroupBySourceCode)
             return;

         var sourceCodeTimeline = event.data.sourceCodeTimeline;
         console.assert(sourceCodeTimeline);
         if (!sourceCodeTimeline)
             return;

         this._pendingRepresentedObjects.push(sourceCodeTimeline);

         this.needsLayout();
     }

     _markerAdded(event)
     {
         this._timelineRuler.addMarker(event.data.marker);
     }

     _recordingReset(event)
     {
         this._timelineRuler.clearMarkers();
         this._timelineRuler.addMarker(this._currentTimeMarker);
     }
 };

 WI.OverviewTimelineView.ReferencePage = WI.ReferencePage.TimelinesTab.EventsView;
	/*
	* Copyright (C) 2013, 2015 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
	* notice, this list of conditions and the following disclaimer in the
	* documentation and/or other materials provided with the distribution.
	*
	* THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
	* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
	* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
	* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
	* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
	* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
	* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
	* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
	* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
	* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
	* THE POSSIBILITY OF SUCH DAMAGE.
	*/

	WI.OverviewTimelineView = class OverviewTimelineView extends WI.TimelineView
	{
	constructor(recording, extraArguments)
	{
	console.assert(recording instanceof WI.TimelineRecording);

	super(recording, extraArguments);

	this._recording = recording;
	this._pendingRepresentedObjects = [];
	this._resourceDataGridNodeMap = new Map;

	if (WI.TimelineRecording.sourceCodeTimelinesSupported() && !this._recording.imported) {
	WI.settings.timelineOverviewGroupBySourceCode.addEventListener(WI.Setting.Event.Changed, this._handleGroupBySourceCodeSettingChanged, this);

	this._groupBySourceCodeNavigationItem = new WI.CheckboxNavigationItem("overview-timeline-group-by-resource", WI.UIString("Group By Resource"), WI.settings.timelineOverviewGroupBySourceCode.value);
	this._groupBySourceCodeNavigationItem.addEventListener(WI.CheckboxNavigationItem.Event.CheckedDidChange, this._handleGroupBySourceCodeNavigationItemCheckedDidChange, this);
	}

	let columns = {name: {}, source: {}, graph: {}};

	columns.name.title = WI.UIString("Name");
	columns.name.width = "20%";
	columns.name.icon = true;
	columns.name.locked = true;
	if (this._shouldGroupBySourceCode)
	columns.name.disclosure = true;

	columns.source.title = WI.UIString("Source");
	columns.source.width = "10%";
	columns.source.icon = true;
	columns.source.locked = true;
	if (this._shouldGroupBySourceCode)
	columns.source.hidden = true;

	this._timelineRuler = new WI.TimelineRuler;
	this._timelineRuler.allowsClippedLabels = true;

	columns.graph.width = "70%";
	columns.graph.headerView = this._timelineRuler;
	columns.graph.locked = true;

	this._dataGrid = new WI.TimelineDataGrid(columns);

	this.setupDataGrid(this._dataGrid);

	this._currentTimeMarker = new WI.TimelineMarker(0, WI.TimelineMarker.Type.CurrentTime);
	this._timelineRuler.addMarker(this._currentTimeMarker);

	this.element.classList.add("overview");
	this.addSubview(this._dataGrid);

	for (let timeline of this._relevantTimelines)
	timeline.addEventListener(WI.Timeline.Event.RecordAdded, this._handleTimelineRecordAdded, this);

	recording.addEventListener(WI.TimelineRecording.Event.SourceCodeTimelineAdded, this._sourceCodeTimelineAdded, this);
	recording.addEventListener(WI.TimelineRecording.Event.MarkerAdded, this._markerAdded, this);
	recording.addEventListener(WI.TimelineRecording.Event.Reset, this._recordingReset, this);

	this._loadExistingRecords();
	}

	// Public

	get secondsPerPixel()
	{
	return this._timelineRuler.secondsPerPixel;
	}

	set secondsPerPixel(x)
	{
	this._timelineRuler.secondsPerPixel = x;
	}

	attached()
	{
	super.attached();

	this._timelineRuler.needsLayout(WI.View.LayoutReason.Resize);
	}

	closed()
	{
	for (let timeline of this._recording.timelines.values())
	timeline.removeEventListener(WI.Timeline.Event.RecordAdded, this._handleTimelineRecordAdded, this);

	this._recording.removeEventListener(WI.TimelineRecording.Event.SourceCodeTimelineAdded, this._sourceCodeTimelineAdded, this);
	this._recording.removeEventListener(WI.TimelineRecording.Event.MarkerAdded, this._markerAdded, this);
	this._recording.removeEventListener(WI.TimelineRecording.Event.Reset, this._recordingReset, this);
	}

	get navigationItems()
	{
	let navigationItems = [];
	if (this._groupBySourceCodeNavigationItem)
	navigationItems.push(this._groupBySourceCodeNavigationItem);
	return navigationItems;
	}

	get selectionPathComponents()
	{
	let dataGridNode = this._dataGrid.selectedNode;
	if (!dataGridNode \|\| dataGridNode.hidden)
	return null;

	let pathComponents = [];

	while (dataGridNode && !dataGridNode.root) {
	console.assert(dataGridNode instanceof WI.TimelineDataGridNode);
	if (dataGridNode.hidden)
	return null;

	let pathComponent = new WI.TimelineDataGridNodePathComponent(dataGridNode);
	pathComponent.addEventListener(WI.HierarchicalPathComponent.Event.SiblingWasSelected, this.dataGridNodePathComponentSelected, this);
	pathComponents.unshift(pathComponent);
	dataGridNode = dataGridNode.parent;
	}

	return pathComponents;
	}

	reset()
	{
	super.reset();

	this._dataGrid.reset();

	this._pendingRepresentedObjects = [];
	this._resourceDataGridNodeMap.clear();
	}

	// Protected

	get showsImportedRecordingMessage()
	{
	return true;
	}

	dataGridNodePathComponentSelected(event)
	{
	let dataGridNode = event.data.pathComponent.timelineDataGridNode;
	console.assert(dataGridNode.dataGrid === this._dataGrid);

	dataGridNode.revealAndSelect();
	}

	layout()
	{
	let oldZeroTime = this._timelineRuler.zeroTime;
	let oldStartTime = this._timelineRuler.startTime;
	let oldEndTime = this._timelineRuler.endTime;
	let oldCurrentTime = this._currentTimeMarker.time;

	this._timelineRuler.zeroTime = this.zeroTime;
	this._timelineRuler.startTime = this.startTime;
	this._timelineRuler.endTime = this.endTime;
	this._currentTimeMarker.time = this.currentTime;

	// The TimelineDataGridNode graphs are positioned with percentages, so they auto resize with the view.
	// We only need to refresh the graphs when the any of the times change.
	if (this.zeroTime !== oldZeroTime \|\| this.startTime !== oldStartTime \|\| this.endTime !== oldEndTime \|\| this.currentTime !== oldCurrentTime) {
	let dataGridNode = this._dataGrid.children[0];
	while (dataGridNode) {
	dataGridNode.refreshGraph();
	dataGridNode = dataGridNode.traverseNextNode(true, null, true);
	}
	}

	this._processPendingRepresentedObjects();
	}

	// Private

	get _relevantTimelines()
	{
	let timelines = [];
	for (let [type, timeline] of this._recording.timelines) {
	if (type === WI.TimelineRecord.Type.RenderingFrame \|\| type === WI.TimelineRecord.Type.CPU \|\| type === WI.TimelineRecord.Type.Memory)
	continue;

	timelines.push(timeline);
	}
	return timelines;
	}

	get _shouldGroupBySourceCode()
	{
	// Always show imported records as non-grouped.
	if (this._recording.imported)
	return false;

	return WI.TimelineRecording.sourceCodeTimelinesSupported() && WI.settings.timelineOverviewGroupBySourceCode.value;
	}

	_loadExistingRecords()
	{
	this._pendingRepresentedObjects = [];
	this._resourceDataGridNodeMap.clear();

	this._dataGrid.removeChildren();

	if (this._shouldGroupBySourceCode) {
	let networkTimeline = this._recording.timelines.get(WI.TimelineRecord.Type.Network);
	if (networkTimeline)
	this._pendingRepresentedObjects.pushAll(networkTimeline.records.map((record) => record.resource));

	this._pendingRepresentedObjects.pushAll(this._recording.sourceCodeTimelines);
	} else {
	for (let timeline of this._relevantTimelines)
	this._pendingRepresentedObjects.pushAll(timeline.records);
	}

	this.needsLayout();
	}

	_compareDataGridNodesByStartTime(a, b)
	{
	function getStartTime(dataGridNode)
	{
	if (dataGridNode instanceof WI.ResourceTimelineDataGridNode)
	return dataGridNode.resource.firstTimestamp;
	if (dataGridNode instanceof WI.SourceCodeTimelineTimelineDataGridNode)
	return dataGridNode.sourceCodeTimeline.startTime;

	console.error("Unknown data grid node.", dataGridNode);
	return 0;
	}

	let result = getStartTime(a) - getStartTime(b);
	if (result)
	return result;

	// Fallback to comparing titles.
	return a.displayName().extendedLocaleCompare(b.displayName());
	}

	_insertDataGridNode(dataGridNode, parentDataGridNode)
	{
	console.assert(dataGridNode);
	console.assert(!dataGridNode.parent);

	if (!parentDataGridNode)
	parentDataGridNode = this._dataGrid;

	parentDataGridNode.insertChild(dataGridNode, insertionIndexForObjectInListSortedByFunction(dataGridNode, parentDataGridNode.children, this._compareDataGridNodesByStartTime));
	}

	_addResourceToDataGridIfNeeded(resource)
	{
	console.assert(resource);
	if (!resource)
	return null;

	// FIXME: replace with this._dataGrid.findDataGridNode(resource) once <https://webkit.org/b/155305> is fixed.
	let dataGridNode = this._resourceDataGridNodeMap.get(resource);
	if (!dataGridNode) {
	let resourceTimelineRecord = this._networkTimeline ? this._networkTimeline.recordForResource(resource) : null;
	if (!resourceTimelineRecord)
	resourceTimelineRecord = new WI.ResourceTimelineRecord(resource);

	dataGridNode = new WI.ResourceTimelineDataGridNode(resourceTimelineRecord, {
	graphDataSource: this,
	includesGraph: true,
	});
	this._resourceDataGridNodeMap.set(resource, dataGridNode);
	}

	if (!dataGridNode.parent) {
	let parentFrame = resource.parentFrame;
	if (!parentFrame)
	return null;

	let expandedByDefault = false;
	if (parentFrame.mainResource === resource \|\| parentFrame.provisionalMainResource === resource) {
	parentFrame = parentFrame.parentFrame;
	expandedByDefault = !parentFrame; // Main frame expands by default.
	}

	if (expandedByDefault)
	dataGridNode.expand();

	let parentDataGridNode = null;
	if (parentFrame) {
	// Find the parent main resource, adding it if needed, to append this resource as a child.
	let parentResource = parentFrame.provisionalMainResource \|\| parentFrame.mainResource;

	parentDataGridNode = this._addResourceToDataGridIfNeeded(parentResource);
	console.assert(parentDataGridNode);
	if (!parentDataGridNode)
	return null;
	}

	this._insertDataGridNode(dataGridNode, parentDataGridNode);
	}

	dataGridNode.refresh();
	return dataGridNode;
	}

	_addSourceCodeTimeline(sourceCodeTimeline)
	{
	let dataGridNode = this._resourceDataGridNodeMap.get(sourceCodeTimeline);
	if (!dataGridNode) {
	dataGridNode = new WI.SourceCodeTimelineTimelineDataGridNode(sourceCodeTimeline, {
	graphDataSource: this,
	});
	this._resourceDataGridNodeMap.set(sourceCodeTimeline, dataGridNode);
	}

	if (!dataGridNode.parent) {
	let parentDataGridNode = sourceCodeTimeline.sourceCodeLocation ? this._addResourceToDataGridIfNeeded(sourceCodeTimeline.sourceCode) : null;
	this._insertDataGridNode(dataGridNode, parentDataGridNode);
	}
	}

	_processPendingRepresentedObjects()
	{
	if (!this._pendingRepresentedObjects.length)
	return;

	for (var representedObject of this._pendingRepresentedObjects) {
	if (this._shouldGroupBySourceCode) {
	if (representedObject instanceof WI.Resource)
	this._addResourceToDataGridIfNeeded(representedObject);
	else if (representedObject instanceof WI.SourceCodeTimeline)
	this._addSourceCodeTimeline(representedObject);
	else
	console.error("Unknown represented object", representedObject);
	} else {
	const options = {
	graphDataSource: this,
	shouldShowPopover: true,
	};

	let dataGridNode = null;
	if (representedObject instanceof WI.ResourceTimelineRecord)
	dataGridNode = new WI.ResourceTimelineDataGridNode(representedObject, options);
	else if (representedObject instanceof WI.LayoutTimelineRecord)
	dataGridNode = new WI.LayoutTimelineDataGridNode(representedObject, options);
	else if (representedObject instanceof WI.MediaTimelineRecord)
	dataGridNode = new WI.MediaTimelineDataGridNode(representedObject, options);
	else if (representedObject instanceof WI.ScriptTimelineRecord)
	dataGridNode = new WI.ScriptTimelineDataGridNode(representedObject, options);
	else if (representedObject instanceof WI.HeapAllocationsTimelineRecord)
	dataGridNode = new WI.HeapAllocationsTimelineDataGridNode(representedObject, options);

	console.assert(dataGridNode, representedObject);
	if (!dataGridNode)
	continue;

	let comparator = (a, b) => {
	return a.record.startTime - b.record.startTime;
	};

	this._dataGrid.insertChild(dataGridNode, insertionIndexForObjectInListSortedByFunction(dataGridNode, this._dataGrid.children, comparator));
	}
	}

	this._pendingRepresentedObjects = [];
	}

	_handleGroupBySourceCodeSettingChanged(event)
	{
	let groupBySourceCode = this._shouldGroupBySourceCode;
	this._dataGrid.disclosureColumnIdentifier = groupBySourceCode ? "name" : undefined;
	this._dataGrid.setColumnVisible("source", !groupBySourceCode);
	if (this._groupBySourceCodeNavigationItem)
	this._groupBySourceCodeNavigationItem.checked = groupBySourceCode;

	this._loadExistingRecords();
	}

	_handleGroupBySourceCodeNavigationItemCheckedDidChange(event)
	{
	WI.settings.timelineOverviewGroupBySourceCode.value = !WI.settings.timelineOverviewGroupBySourceCode.value;
	}

	_handleTimelineRecordAdded(event)
	{
	let {record} = event.data;

	if (this._shouldGroupBySourceCode) {
	if (event.target.type !== WI.TimelineRecord.Type.Network)
	return;

	console.assert(record instanceof WI.ResourceTimelineRecord);

	this._pendingRepresentedObjects.push(record.resource);
	} else
	this._pendingRepresentedObjects.push(record);

	this.needsLayout();
	}

	_sourceCodeTimelineAdded(event)
	{
	if (!this._shouldGroupBySourceCode)
	return;

	var sourceCodeTimeline = event.data.sourceCodeTimeline;
	console.assert(sourceCodeTimeline);
	if (!sourceCodeTimeline)
	return;

	this._pendingRepresentedObjects.push(sourceCodeTimeline);

	this.needsLayout();
	}

	_markerAdded(event)
	{
	this._timelineRuler.addMarker(event.data.marker);
	}

	_recordingReset(event)
	{
	this._timelineRuler.clearMarkers();
	this._timelineRuler.addMarker(this._currentTimeMarker);
	}
	};

	WI.OverviewTimelineView.ReferencePage = WI.ReferencePage.TimelinesTab.EventsView;