Merge branch 'master' into simeonoff/fix-8718

Author: rkaraivanov

projects/igniteui-angular/src/lib/data-operations/filtering-condition.ts

@@ -548,7 +548,7 @@ export class IgxStringFilteringOperand extends IgxFilteringOperand {
      * @memberof IgxStringFilteringOperand
      */
     public static applyIgnoreCase(a: string, ignoreCase: boolean): string {
-        a = a || '';
+        a = a ?? '';
         // bulletproof
         return ignoreCase ? ('' + a).toLowerCase() : a;
     }

projects/igniteui-angular/src/lib/grids/grid/grid-filtering.spec.ts

@@ -649,6 +649,16 @@ describe('IgxGrid - Filtering actions #grid', () => {
         expect(grid.rowList.length).toEqual(1);
     }));
 
+    it('should exclude null and undefined values when filter by \'false\'', fakeAsync(() => {
+        expect(grid.rowList.length).toEqual(8);
+
+        grid.filter('Released', false, IgxStringFilteringOperand.instance().condition('equals'), true);
+        fix.detectChanges();
+        expect(grid.rowList.length).toEqual(2);
+        expect(grid.getCellByColumn(0, 'Released').value).toBe(false);
+        expect(grid.getCellByColumn(1, 'Released').value).toBe(false);
+    }));
+
     it('should correctly apply multiple filtering through API', fakeAsync(() => {
         const gridExpressionsTree = new FilteringExpressionsTree(FilteringLogic.And);
         gridExpressionsTree.filteringOperands = [