env for that thread to fix occasional assertion failure that indicated
I was using the wrong env occasionally. I'm not super confident in
this because I've seen the env for a thread change, but that could be
due to reuse of the thread id.
their games being drawn (no BoardActivity around) break the two
android-only callbacks out of UtilCtxt and into a new JNIUtils
interface that then requires new handing in C.
