DevTools: Disable timeline network pane resizer when network group is collapsed.

third_party/WebKit/Source/devtools/front_end/timeline/TimelineFlameChartView.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.
 
 Timeline.FlameChartStyle = {
   textColor: '#333'
 };
 
 /**
  * @enum {symbol}
@@ skipping 113 matching lines @@
     this._mainView.alwaysShowVerticalScroll();
     this._mainView.enableRuler(false);
 
     var networkViewGroupExpansionSetting =
         Common.settings.createSetting('timelineFlamechartNetworkViewGroupExpansion', {});
     this._networkDataProvider = new Timeline.TimelineFlameChartNetworkDataProvider(this._model);
     this._networkView = new PerfUI.FlameChart(this._networkDataProvider, this, networkViewGroupExpansionSetting);
     this._networkView.alwaysShowVerticalScroll();
     networkViewGroupExpansionSetting.addChangeListener(this.resizeToPreferredHeights.bind(this));
 
-    const networkPane = new UI.VBox();
-    networkPane.setMinimumSize(23, 23);
-    this._networkView.show(networkPane.element);
-    this._splitResizer = networkPane.element.createChild('div', 'timeline-flamechart-resizer');
-    this._splitWidget.hideDefaultResizer();
+    this._networkPane = new UI.VBox();
+    this._networkPane.setMinimumSize(23, 23);
+    this._networkView.show(this._networkPane.element);
+    this._splitResizer = this._networkPane.element.createChild('div', 'timeline-flamechart-resizer');
+    this._splitWidget.hideDefaultResizer(true);
     this._splitWidget.installResizer(this._splitResizer);
 
     this._splitWidget.setMainWidget(this._mainView);
-    this._splitWidget.setSidebarWidget(networkPane);
+    this._splitWidget.setSidebarWidget(this._networkPane);
 
     if (Runtime.experiments.isEnabled('timelineMultipleMainViews')) {
       // Create top level properties splitter.
       this._detailsSplitWidget = new UI.SplitWidget(false, true, 'timelinePanelDetailsSplitViewState');
       this._detailsSplitWidget.element.classList.add('timeline-details-split');
       this._detailsView =
           new Timeline.TimelineDetailsView(timelineModel, frameModel, filmStripModel, filters, delegate);
       this._detailsSplitWidget.installResizer(this._detailsView.headerElement());
       this._detailsSplitWidget.setMainWidget(this._splitWidget);
       this._detailsSplitWidget.setSidebarWidget(this._detailsView);
@@ skipping 161 matching lines @@
   /**
    * @param {!PerfUI.FlameChartDataProvider} dataProvider
    * @param {!Common.Event} event
    */
   _onEntrySelected(dataProvider, event) {
     var entryIndex = /** @type{number} */ (event.data);
     this._delegate.select(dataProvider.createSelection(entryIndex));
   }
 
   resizeToPreferredHeights() {
+    this._networkPane.element.classList.toggle(
+        'timeline-network-resizer-disabled', !this._networkDataProvider.isExpanded());
     this._splitWidget.setSidebarSize(
         this._networkDataProvider.preferredHeight() + this._splitResizer.clientHeight + PerfUI.FlameChart.HeaderHeight +
-        3);
+        2);
   }
 };
 
 /**
  * @unrestricted
  */
 Timeline.TimelineFlameChartView.Selection = class {
   /**
    * @param {!Timeline.TimelineSelection} selection
    * @param {number} entryIndex
    */
   constructor(selection, entryIndex) {
     this.timelineSelection = selection;
     this.entryIndex = entryIndex;
   }
 };