fix(ColChooser): #2530 Unsubscribe from valueChange.

Author: gedinakova

projects/igniteui-angular/src/lib/grid-common/column-hiding/column-chooser-item-base.ts

@@ -1,4 +1,4 @@
-import { EventEmitter, Input, Output } from '@angular/core';
+import { EventEmitter, Input, Output, OnDestroy } from '@angular/core';
 
 export interface IValueChangedEventArgs {
     oldValue: any;
@@ -47,7 +47,7 @@ export abstract class ItemPropertyValueChanged {
     }
 }
 
-export class ColumnChooserItemBase extends ItemPropertyValueChanged {
+export class ColumnChooserItemBase extends ItemPropertyValueChanged implements OnDestroy {
     @Input()
     get column() {
         return this.object;
@@ -69,6 +69,10 @@ export class ColumnChooserItemBase extends ItemPropertyValueChanged {
         super(prop);
     }
 
+    ngOnDestroy(): void {
+        this.valueChanged.unsubscribe();
+    }
+
     get name() {
         return (this.column) ? ((this.column.header) ? this.column.header : this.column.field) : '';
     }