fix: test failure

Author: crisbeto

src/lib/autocomplete/autocomplete-trigger.ts

@@ -18,7 +18,7 @@ import {
   ScrollStrategy,
 } from '@angular/cdk/overlay';
 import {TemplatePortal} from '@angular/cdk/portal';
-import {filter, first, map, RxChain, switchMap, doOperator, delay} from '@angular/cdk/rxjs';
+import {filter, first, RxChain, switchMap, doOperator, delay} from '@angular/cdk/rxjs';
 import {
   ChangeDetectorRef,
   Directive,

src/lib/autocomplete/autocomplete.spec.ts

@@ -1568,6 +1568,7 @@ describe('MatAutocomplete', () => {
     fixture.componentInstance.states.push('Puerto Rico');
     fixture.detectChanges();
     tick();
+    fixture.detectChanges();
 
     let options = overlayContainerElement.querySelectorAll('mat-option') as NodeListOf<HTMLElement>;
     let spy = fixture.componentInstance.optionSelected;