fix(menu): properly handle spacebar events (#1533)

Closes #1175

e2e/components/menu/menu.e2e.ts

@@ -73,11 +73,16 @@ describe('menu', () => {
       page.pressKey(protractor.Key.TAB);
     });
 
-    it('should auto-focus the first item when opened with keyboard', () => {
+    it('should auto-focus the first item when opened with ENTER', () => {
       page.pressKey(protractor.Key.ENTER);
       page.expectFocusOn(page.items(0));
     });
 
+    it('should auto-focus the first item when opened with SPACE', () => {
+      page.pressKey(protractor.Key.SPACE);
+      page.expectFocusOn(page.items(0));
+    });
+
     it('should not focus the first item when opened with mouse', () => {
       page.trigger().click();
       page.expectFocusOn(page.trigger());

src/lib/core/keyboard/keycodes.ts

@@ -10,4 +10,5 @@ export const RIGHT_ARROW = 39;
 export const LEFT_ARROW = 37;
 
 export const ENTER = 13;
+export const SPACE = 32;
 export const TAB = 9;

src/lib/menu/menu-trigger.ts

@@ -14,6 +14,7 @@ import {MdMenu} from './menu-directive';
 import {MdMenuMissingError} from './menu-errors';
 import {
     ENTER,
+    SPACE,
     Overlay,
     OverlayState,
     OverlayRef,
@@ -172,7 +173,7 @@ export class MdMenuTrigger implements AfterViewInit, OnDestroy {
 
   // TODO: internal
   _handleKeydown(event: KeyboardEvent): void {
-    if (event.keyCode === ENTER) {
+    if (event.keyCode === ENTER || event.keyCode === SPACE) {
       this._openedFromKeyboard = true;
     }
   }