app,io/router: map Androids' DPAD_CENTER to a click

Mapping it to key.NameReturn confuses widgets such as Editor that
treats clicks separate from return key presses.

Signed-off-by: Elias Naur <mail@eliasnaur.com>

app/os_android.go

@@ -903,7 +903,7 @@ func convertKeyCode(code C.jint) (string, bool) {
 		n = key.NameDeleteBackward
 	case C.AKEYCODE_NUMPAD_ENTER:
 		n = key.NameEnter
-	case C.AKEYCODE_ENTER, C.AKEYCODE_DPAD_CENTER:
+	case C.AKEYCODE_ENTER:
 		n = key.NameReturn
 	case C.AKEYCODE_CTRL_LEFT, C.AKEYCODE_CTRL_RIGHT:
 		n = key.NameCtrl
@@ -932,6 +932,8 @@ func Java_org_gioui_GioView_onKeyEvent(env *C.JNIEnv, class C.jclass, handle C.j
 			w.callbacks.MoveFocus(router.FocusLeft)
 		case C.AKEYCODE_DPAD_RIGHT:
 			w.callbacks.MoveFocus(router.FocusRight)
+		case C.AKEYCODE_DPAD_CENTER:
+			w.callbacks.ClickFocus()
 		}
 	}
 	if n, ok := convertKeyCode(keyCode); ok {

app/window.go

@@ -510,6 +510,12 @@ func (c *callbacks) MoveFocus(dir router.FocusDirection) {
 	c.w.updateAnimation(c.d)
 }
 
+func (c *callbacks) ClickFocus() {
+	c.w.queue.q.ClickFocus()
+	c.w.setNextFrame(time.Time{})
+	c.w.updateAnimation(c.d)
+}
+
 func (e *editorState) Replace(r key.Range, text string) {
 	if r.Start > r.End {
 		r.Start, r.End = r.End, r.Start