142     for (const panel of panels) {  constant
143       if (panel.attrs.id !== undefined) {
144         tracks.push(panel.attrs.id);
147       if (panel.attrs.trackGroupId !== undefined) {
148         const trackGroup = globals.state.trackGroups[panel.attrs.trackGroupId];  constant
151           tracks.push(panel.attrs.trackGroupId);
220     const renderPanel = (panel: m.Vnode) => perfDebug() ?
222           {key: panel.key},
223           [panel, m('.debug-panel-border', {key: 'debug-panel-border'})]) :
224         m('.panel', {key: panel.key}, panel);
341       const panel = panels[i];  constant
345       if (!isPanelVNode(panel)) {
350       const p = panel as PanelVNode<{}>;
438       panelIndex: number, panel: Panel, renderTime: number,
441     let renderStats = this.panelPerfStats.get(panel);
444       this.panelPerfStats.set(panel, renderStats);