VIRO-2242: use bloom threshold of 0.5 for bloom tests
VIRO-2242: use bloom threshold of 0.5 for bloom tests

The bloom threshold of 1.0 would either bloom or not
bloom, depending on the device, since it’s right on the
boundary of what brightness creates bloom (e.g. a light
with brightness 1.0 on a bright surface results in a brightness
of 1.0.


Former-commit-id: 63089847ae7fd2bdbed8ac9bc18661123af8579f
viromedia/viro,viromedia/viro,viromedia/viro,viromedia/viro