Remove private constructor.

Author: MKirova

projects/igniteui-angular/src/lib/data-operations/pivot-strategy.ts

@@ -12,8 +12,6 @@ export interface IPivotDimensionStrategy {
 export class NoopPivotDimensionsStrategy implements IPivotDimensionStrategy {
     private static _instance: NoopPivotDimensionsStrategy = null;
 
-    private constructor() {  }
-
     public static instance() {
         return this._instance || (this._instance = new NoopPivotDimensionsStrategy());
     }
@@ -27,8 +25,6 @@ export class NoopPivotDimensionsStrategy implements IPivotDimensionStrategy {
 export class PivotRowDimensionsStrategy implements IPivotDimensionStrategy {
     private static _instance: PivotRowDimensionsStrategy = null;
 
-    private constructor() {  }
-
     public static instance() {
         return this._instance || (this._instance = new PivotRowDimensionsStrategy());
     }
@@ -84,8 +80,6 @@ export class PivotRowDimensionsStrategy implements IPivotDimensionStrategy {
 export class PivotColumnDimensionsStrategy implements IPivotDimensionStrategy {
     private static _instance: PivotRowDimensionsStrategy = null;
 
-    private constructor() {  }
-
     public static instance() {
         return this._instance || (this._instance = new PivotColumnDimensionsStrategy());
     }

src/app/pivot-grid-noop/pivot-grid-noop.sample.ts

@@ -1,5 +1,22 @@
 import { Component, ViewChild } from '@angular/core';
-import { IgxNumberSummaryOperand, IgxPivotGridComponent, IPivotConfiguration, NoopPivotDimensionsStrategy } from 'igniteui-angular';
+import { IgxNumberSummaryOperand, IgxPivotGridComponent, IPivotConfiguration, IPivotDimension, IPivotDimensionStrategy,
+     IPivotValue,
+     NoopPivotDimensionsStrategy } from 'igniteui-angular';
+
+
+
+export class MyRowStrategy extends NoopPivotDimensionsStrategy {
+    public process(collection: any[], _: IPivotDimension[], __: IPivotValue[]): any[] {
+        return collection;
+    }
+}
+
+export class MyColumnStrategy extends NoopPivotDimensionsStrategy {
+    public process(collection: any[], _: IPivotDimension[], __: IPivotValue[]): any[] {
+        return collection;
+    }
+}
+
 
 @Component({
     providers: [],
@@ -10,7 +27,6 @@ import { IgxNumberSummaryOperand, IgxPivotGridComponent, IPivotConfiguration, No
 
 export class PivotGridNoopSampleComponent {
     @ViewChild('grid1', { static: true }) public grid1: IgxPivotGridComponent;
-
     public pivotConfigHierarchy: IPivotConfiguration = {
         columnStrategy: NoopPivotDimensionsStrategy.instance(),
         rowStrategy: NoopPivotDimensionsStrategy.instance(),