fix: test failure

Author: crisbeto

src/lib/autocomplete/autocomplete.spec.ts

@@ -1487,6 +1487,8 @@ describe('MdAutocomplete', () => {
 
     fixture.componentInstance.states.push('Puerto Rico');
     fixture.detectChanges();
+    tick();
+    fixture.detectChanges();
 
     let options = overlayContainerElement.querySelectorAll('md-option') as NodeListOf<HTMLElement>;
     let spy = fixture.componentInstance.optionSelected;