tree b175f459ed78afa307f9337426edd35bb8330230
parent 6c1e8b815b1ed5d2437e5c8b8a36a144307ac97b
author Arman Uguray <armansito@google.com> 1713393580 -0700
committer Arman Uguray <armansito@google.com> 1713574403 -0700

[backdrop_dyn] Handle upstream pipeline failure

Following #537 it is possible for the flatten stage to fail and flag
a failure. In some cases this can cause invalid / corrupt bounding box
data to propagate downstream, leading to a hang in the per-tile
backdrop calculation loop.

Triggering this is highly subtle, so I don't have a test case as part of
vello scenes that can reliably reproduce this. Regardless, it makes
sense to check for the upstream failures and terminate the work in
general.