Function openPanel

src/material/autocomplete/autocomplete.spec.ts:2200–2204

()

      fixture.detectChanges();
      let inputReference = fixture.debugElement.query(By.css('.mdc-text-field'))!.nativeElement;
      let openPanel = async () => {
        fixture.componentInstance.trigger.openPanel();
        fixture.detectChanges();
        fixture.detectChanges();
      };

      // Push the autocomplete trigger down so it won't have room to open below.
      inputReference.style.bottom = '0';