web/chart: fix sample (#909)

web/charts/lib/bar_chart/spark_bar.dart

@@ -25,10 +25,10 @@ class SparkBar extends StatelessWidget {
   final List<charts.Series> seriesList;
   final bool animate;
 
-  SparkBar(this.seriesList, {this.animate});
+  const SparkBar(this.seriesList, {this.animate, Key key}) : super(key: key);
 
   factory SparkBar.withSampleData() {
-    return new SparkBar(
+    return SparkBar(
       _createSampleData(),
       // Disable animations for image tests.
       animate: false,
@@ -40,29 +40,29 @@ class SparkBar extends StatelessWidget {
   // It is used for creating random series data to demonstrate animation in
   // the example app only.
   factory SparkBar.withRandomData() {
-    return new SparkBar(_createRandomData());
+    return SparkBar(_createRandomData());
   }
 
   /// Create random data.
   static List<charts.Series<OrdinalSales, String>> _createRandomData() {
-    final random = new Random();
+    final random = Random();
 
     final globalSalesData = [
-      new OrdinalSales('2007', random.nextInt(100)),
-      new OrdinalSales('2008', random.nextInt(100)),
-      new OrdinalSales('2009', random.nextInt(100)),
-      new OrdinalSales('2010', random.nextInt(100)),
-      new OrdinalSales('2011', random.nextInt(100)),
-      new OrdinalSales('2012', random.nextInt(100)),
-      new OrdinalSales('2013', random.nextInt(100)),
-      new OrdinalSales('2014', random.nextInt(100)),
-      new OrdinalSales('2015', random.nextInt(100)),
-      new OrdinalSales('2016', random.nextInt(100)),
-      new OrdinalSales('2017', random.nextInt(100)),
+      OrdinalSales('2007', random.nextInt(100)),
+      OrdinalSales('2008', random.nextInt(100)),
+      OrdinalSales('2009', random.nextInt(100)),
+      OrdinalSales('2010', random.nextInt(100)),
+      OrdinalSales('2011', random.nextInt(100)),
+      OrdinalSales('2012', random.nextInt(100)),
+      OrdinalSales('2013', random.nextInt(100)),
+      OrdinalSales('2014', random.nextInt(100)),
+      OrdinalSales('2015', random.nextInt(100)),
+      OrdinalSales('2016', random.nextInt(100)),
+      OrdinalSales('2017', random.nextInt(100)),
     ];
 
     return [
-      new charts.Series<OrdinalSales, String>(
+      charts.Series<OrdinalSales, String>(
         id: 'Global Revenue',
         domainFn: (OrdinalSales sales, _) => sales.year,
         measureFn: (OrdinalSales sales, _) => sales.sales,
@@ -74,7 +74,7 @@ class SparkBar extends StatelessWidget {
 
   @override
   Widget build(BuildContext context) {
-    return new charts.BarChart(
+    return charts.BarChart(
       seriesList,
       animate: animate,
 
@@ -83,45 +83,45 @@ class SparkBar extends StatelessWidget {
       /// The NoneRenderSpec only draws an axis line (and even that can be hidden
       /// with showAxisLine=false).
       primaryMeasureAxis:
-          new charts.NumericAxisSpec(renderSpec: new charts.NoneRenderSpec()),
+          const charts.NumericAxisSpec(renderSpec: charts.NoneRenderSpec()),
 
       /// This is an OrdinalAxisSpec to match up with BarChart's default
       /// ordinal domain axis (use NumericAxisSpec or DateTimeAxisSpec for
       /// other charts).
-      domainAxis: new charts.OrdinalAxisSpec(
+      domainAxis: const charts.OrdinalAxisSpec(
           // Make sure that we draw the domain axis line.
           showAxisLine: true,
           // But don't draw anything else.
-          renderSpec: new charts.NoneRenderSpec()),
+          renderSpec: charts.NoneRenderSpec()),
 
       // With a spark chart we likely don't want large chart margins.
       // 1px is the smallest we can make each margin.
-      layoutConfig: new charts.LayoutConfig(
-          leftMarginSpec: new charts.MarginSpec.fixedPixel(0),
-          topMarginSpec: new charts.MarginSpec.fixedPixel(0),
-          rightMarginSpec: new charts.MarginSpec.fixedPixel(0),
-          bottomMarginSpec: new charts.MarginSpec.fixedPixel(0)),
+      layoutConfig: charts.LayoutConfig(
+          leftMarginSpec: charts.MarginSpec.fixedPixel(0),
+          topMarginSpec: charts.MarginSpec.fixedPixel(0),
+          rightMarginSpec: charts.MarginSpec.fixedPixel(0),
+          bottomMarginSpec: charts.MarginSpec.fixedPixel(0)),
     );
   }
 
   /// Create series list with single series
   static List<charts.Series<OrdinalSales, String>> _createSampleData() {
     final globalSalesData = [
-      new OrdinalSales('2007', 3100),
-      new OrdinalSales('2008', 3500),
-      new OrdinalSales('2009', 5000),
-      new OrdinalSales('2010', 2500),
-      new OrdinalSales('2011', 3200),
-      new OrdinalSales('2012', 4500),
-      new OrdinalSales('2013', 4400),
-      new OrdinalSales('2014', 5000),
-      new OrdinalSales('2015', 5000),
-      new OrdinalSales('2016', 4500),
-      new OrdinalSales('2017', 4300),
+      OrdinalSales('2007', 3100),
+      OrdinalSales('2008', 3500),
+      OrdinalSales('2009', 5000),
+      OrdinalSales('2010', 2500),
+      OrdinalSales('2011', 3200),
+      OrdinalSales('2012', 4500),
+      OrdinalSales('2013', 4400),
+      OrdinalSales('2014', 5000),
+      OrdinalSales('2015', 5000),
+      OrdinalSales('2016', 4500),
+      OrdinalSales('2017', 4300),
     ];
 
     return [
-      new charts.Series<OrdinalSales, String>(
+      charts.Series<OrdinalSales, String>(
         id: 'Global Revenue',
         domainFn: (OrdinalSales sales, _) => sales.year,
         measureFn: (OrdinalSales sales, _) => sales.sales,