This makes existing tests slightly broken, which is good (if it
wouldn't, the thresholds would be too huge). Since the addition of ES3.2
geometry shaders (which broke this) happened long before there were
rendering tests for shaders, this breakage wasn't caught until now. Of
course proper tests would include the perspective case from the previous
commit since the very beginning, but that's hard to do when you're
testing long after the code was written.
The test files are now RLE-encoded, which makes them significantly
smaller (tho I assume Git would further compress both anyway). Not
updating existing files to RLE yet to avoid repo history bloat, doing
that the next time they get changed.