fix(autocomplete): restore focus after emitting option selected event

Currently we restore focus to the input and then we emit the change event, but we have a report that it may be making some use cases more difficult. From what I can tell, this shouldn't have much of an impact on existing users so these changes swap the order so that the focus event is last.

Fixes #18650.

Author: crisbeto

src/material/autocomplete/autocomplete-trigger.ts

@@ -592,12 +592,14 @@ export class MatAutocompleteTrigger implements ControlValueAccessor, AfterViewIn
    * stemmed from the user.
    */
   private _setValueAndClose(event: MatOptionSelectionChange | null): void {
-    if (event && event.source) {
-      this._clearPreviousSelectedOption(event.source);
-      this._setTriggerValue(event.source.value);
-      this._onChange(event.source.value);
+    const source = event && event.source;
+
+    if (source) {
+      this._clearPreviousSelectedOption(source);
+      this._setTriggerValue(source.value);
+      this._onChange(source.value);
+      this.autocomplete._emitSelectEvent(source);
       this._element.nativeElement.focus();
-      this.autocomplete._emitSelectEvent(event.source);
     }
 
     this.closePanel();

src/material/autocomplete/autocomplete.spec.ts

@@ -2468,6 +2468,28 @@ describe('MatAutocomplete', () => {
     expect(event.option.value).toBe('Washington');
   }));
 
+  it('should refocus the input after the selection event is emitted', fakeAsync(() => {
+    const events: string[] = [];
+    const fixture = createComponent(AutocompleteWithSelectEvent);
+    fixture.detectChanges();
+    const input = fixture.nativeElement.querySelector('input');
+
+    fixture.componentInstance.trigger.openPanel();
+    zone.simulateZoneExit();
+    fixture.detectChanges();
+
+    const options =
+        overlayContainerElement.querySelectorAll('mat-option') as NodeListOf<HTMLElement>;
+    spyOn(input, 'focus').and.callFake(() => events.push('focus'));
+    fixture.componentInstance.optionSelected.and.callFake(() => events.push('select'));
+
+    options[1].click();
+    tick();
+    fixture.detectChanges();
+
+    expect(events).toEqual(['select', 'focus']);
+  }));
+
   it('should emit an event when a newly-added option is selected', fakeAsync(() => {
     let fixture = createComponent(AutocompleteWithSelectEvent);