Move webgl_conformance tests out of the CrOS VM specific pool.

As part of crbug.com/1132206, I'm merging the CrOS VM pool to the main
chromium.tests pool. A couple of suites have already moved over, and the
isolate-input overhead looks pretty similar to those that haven't
switched after I bumped max cache size in crrev.com/i/3338983

So this continues with the merging by moving over webgl_conformance
tests. This suite takes up about 20% of the current run time in the
current VM pool. So I'll move 20% of the VM pool's bots to the main pool
in crrev.com/i/3344206 prior to landing this.

Bug: 1132206
Change-Id: I05ae7b309853102eb0a9dccb5017349d85b74169
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2481291
Reviewed-by: Brian Sheedy <bsheedy@chromium.org>
Commit-Queue: Ben Pastene <bpastene@chromium.org>
Cr-Commit-Position: refs/heads/master@{#818105}
GitOrigin-RevId: 2ea8ba50dfa58ef34db909a5a5dc8341cab27966
4 files changed