930135 - test-displayport-2.html reftest doesn't work properly in ipc mode if not run with other tests

Status: NEW

(Core :: Layout, defect)

Description

[Nathan Froyd [:froydnj]]

Running:

_virtualenv/bin/python -u _tests/reftest/runreftest.py  --setenv MOZ_DISABLE_CONTEXT_SHARING_GLX=1 --setenv MOZ_OMTC_ENABLED=1 --extra-profile-file=./dist/plugins --symbols-path=./dist/crashreporter-symbols --timeout=20 --setpref=browser.tabs.remote=true --setpref=layers.offmainthreadcomposition.testing.enabled=true --this-chunk=20 --total-chunks=32 /home/froydnj/src/mozilla-central-official/layout/reftests/reftest-sanity/reftest.list

causes test-displayport-2.html to fail.  The combinations of:

--this-chunk=10 --total-chunks=16
--this-chunk=5 --total-chunks=8
--this-chunk=3 --total-chunks=4

also cause the test to fail.  However, omitting --this-chunk and --total-chunk causes the test to pass.

This is unexpected, and it's also blocking running reftests in parallel, which relies upon splitting the reftests using --this-chunk and --total-chunks.