SurfaceTexture: add some GL->GL tests.

This change adds some tests to verify streaming images from one GL
thread to another via SurfaceTexture.  Currently the tests do not
validate the correctness of the streamed images, but rather simply
verify that this streaming does not cause a deadlock.  3 of the 4 tests
are currently disabled because they do cause deadlocks on some devices.

Change-Id: I5677942053190063b97f370dba96c116711bc3bb