Add additional abanoned checks in read pixels.

The checks for PMUPM conversions can cause us to abanon the context when
work is submitted to the GPU for its tests. So after calling that
function we need to make sure we're still in a valid state.

Bug: chromium:1205797
Change-Id: I652da7fc9bb230fcd141c890d312fce37fc42e22
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/439817
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Greg Daniel <egdaniel@google.com>
2 files changed