Minor fixes

public/app/plugins/panel/piechart/PieChartPanelEditor.tsx

@@ -5,8 +5,6 @@ import ValueOptions from './ValueOptions';
 import { PiechartOptions } from './types';
 
 export default class PiechartPanelOptions extends PureComponent<PanelEditorProps<PiechartOptions>> {
-  static defaultProps = defaultProps;
-
   render() {
     const { onChange, options } = this.props;
 

public/app/plugins/panel/piechart/PiechartPanel.tsx

@@ -18,7 +18,7 @@ export class PiechartPanel extends PureComponent<Props> {
     const { panelData, width, height, options } = this.props;
     const { valueOptions } = options;
 
-    let datapoints: PieChartDataPoint[] = [];
+    const datapoints: PieChartDataPoint[] = [];
     if (panelData.timeSeries) {
       const vmSeries = processTimeSeries({
         timeSeries: panelData.timeSeries,