[ADF-3082] Task Filter - Custom Task filters don't work (#3402)

* [ADF-3082] Custom Task filters don't work.

* Added an sorting input to the datatable.
* Updated documentation for the recent changes.
* Added testcases for the recent changes.

* [ADF-3082] Custom Task filters don't work

* Added a sorting input to the datatable
* Added testcases to the recent changes.
* Updated doc for the recent changes.

* * Refactored task/process list dataSort.

* * Refactored process/task list datasort method

lib/process-services/task-list/components/task-list.component.ts

@@ -136,6 +136,7 @@ export class TaskListComponent implements OnChanges, AfterContentInit, Paginated
     size: number = PaginationComponent.DEFAULT_PAGINATION.maxItems;
 
     isLoading: boolean = true;
+    sorting: any[] = ['created', 'desc'];
 
     /**
      * Toggles custom data source mode.
@@ -301,6 +302,14 @@ export class TaskListComponent implements OnChanges, AfterContentInit, Paginated
         }
     }
 
+    /**
+     * Return the sorting order
+     * Sort the tasks based on current value of 'sort' property
+     */
+    get dataSort(): any[] {
+        return this.sort ? this.sort.split('-') : this.sorting;
+    }
+
     /**
      * Return the current id
      */