fix(ivy): stub TestBed.compileComponents implementation (#26506)

PR Close #26506

packages/core/test/test_bed_async_spec.ts

@@ -0,0 +1,18 @@
+/**
+ * @license
+ * Copyright Google Inc. All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.io/license
+ */
+
+import {TestBed} from '@angular/core/testing/src/test_bed';
+import {AsyncTestCompleter, ddescribe, describe, inject, it} from '@angular/core/testing/src/testing_internal';
+
+describe('TestBed with async processing', () => {
+
+  beforeEach(() => { TestBed.resetTestingModule(); });
+
+  it('should allow injecting AsyncTestCompleter',
+     inject([AsyncTestCompleter], (async: AsyncTestCompleter) => { async.done(); }));
+});