chore(*): Fix issue with initrtially pinned rows.

Author: MKirova

projects/igniteui-angular/src/lib/grids/grid-base.directive.ts

@@ -2670,6 +2670,14 @@ export class IgxGridBaseDirective extends DisplayDensityBase implements
         return this._pinnedRecordIDs.length > 0;
     }
 
+    /**
+    * @hidden
+    * @internal
+    */
+    public get pinnedRecordsCount() {
+        return this._pinnedRecordIDs.length;
+    }
+
     private keydownHandler = (event) => {
         const key = event.key.toLowerCase();
         if ((isNavigationKey(key) && event.keyCode !== 32) || key === 'tab' || key === 'pagedown' || key === 'pageup') {

projects/igniteui-angular/src/lib/grids/grid/grid.pipes.ts

@@ -103,7 +103,7 @@ export class IgxGridPagingPipe implements PipeTransform {
         if (!this.gridAPI.grid.paging) {
             return collection;
         }
-        const _perPage = perPage - this.gridAPI.grid.pinnedRows.length;
+        const _perPage = perPage - this.gridAPI.grid.pinnedRecordsCount;
         const state = {
             index: page,
             recordsPerPage: _perPage