Run the WebGL2 conformance GL tests against the passthrough cmd decoder.

ANGLE's GL backend will likely only be released in conjuction with the
passthrough command decoder.

TBR=kbr@chromium.org
BUG=693090

Cq-Include-Trybots: luci.chromium.try:android_optional_gpu_tests_rel;luci.chromium.try:linux_optional_gpu_tests_rel;luci.chromium.try:mac_optional_gpu_tests_rel;luci.chromium.try:win_optional_gpu_tests_rel
Change-Id: I92df6a32eae8a8266454ab6312c2a3b56c2cf9e4
Reviewed-on: https://chromium-review.googlesource.com/984372
Commit-Queue: Geoff Lang <geofflang@chromium.org>
Reviewed-by: Zhenyao Mo <zmo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#552084}
2 files changed