[chart.js] Add missing legend label configuration options (#23157)

types/chart.js/chart.js-tests.ts

@@ -45,7 +45,14 @@ const chart: Chart = new Chart(new CanvasRenderingContext2D(), {
                 }
             }]
         },
-        plugins: { arbitraryPlugin: {option: "value"} }
+        plugins: { arbitraryPlugin: {option: "value"} },
+        legend: {
+            display: true,
+            labels: {
+                usePointStyle: true,
+                padding: 40
+            }
+        },
     }
 });
 chart.update();

types/chart.js/index.d.ts

@@ -8,6 +8,7 @@
 //                 Joseph Page <https://github.com/josefpaij>
 //                 Dan Manastireanu <https://github.com/danmana>
 //                 Guillaume Rodriguez <https://github.com/guillaume-ro-fr>
+//                 Sergey Rubanov <https://github.com/chicoxyzzy>
 // Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
 // TypeScript Version: 2.3
 
@@ -119,6 +120,7 @@ declare namespace Chart {
         lineJoin?: string;
         lineWidth?: number;
         strokeStyle?: string;
+        pointStyle?: PointStyle;
     }
 
     interface ChartTooltipItem {
@@ -231,6 +233,8 @@ declare namespace Chart {
         fontFamily?: string;
         padding?: number;
         generateLabels?(chart: any): any;
+        filter?(item: ChartLegendItem, data: ChartData): any;
+        usePointStyle?: boolean;
     }
 
     interface ChartTooltipOptions {