Fix race condition and disable call.

1. A dispatch event can happen as soon you call enabled,
and we won't be ready to receive it. Also add error checks
and not crash if such a thing happens.

2. Java layer shouldn't call disable on the native layer
for trigger sensors. Native layer will clean up on its own.

b/8165631

Change-Id: Icbe76bd1f50632c0bcb0b3b04975b2c2f20ff36b