app: fix comparison of keys' direction

KeyEvent's getAction returns ACTION_DOWN (0), ACTION_UP (1) or
other values, and not AKEY_STATE_DOWN (1) or AKEY_STATE_UP (0).
This change fixes the wrong comparison.

Fixes golang/go#37374

Change-Id: Ia65ac881e57cc29d4bdde2365e177c2b4499a2d9
Reviewed-on: https://go-review.googlesource.com/c/mobile/+/220538
Run-TryBot: Hajime Hoshi <hajimehoshi@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Hyang-Ah Hana Kim <hyangah@gmail.com>
diff --git a/app/android.go b/app/android.go
index 213e31d..a0c3312 100644
--- a/app/android.go
+++ b/app/android.go
@@ -436,9 +436,9 @@
 		Code: convAndroidKeyCode(int32(C.AKeyEvent_getKeyCode(e))),
 	}
 	switch C.AKeyEvent_getAction(e) {
-	case C.AKEY_STATE_DOWN:
+	case C.AKEY_EVENT_ACTION_DOWN:
 		k.Direction = key.DirPress
-	case C.AKEY_STATE_UP:
+	case C.AKEY_EVENT_ACTION_UP:
 		k.Direction = key.DirRelease
 	default:
 		k.Direction = key.DirNone