media/gpu/vdatest: remove --rendering_warm_up option

This option was a no-op, and is being removed from autotests.

BUG=819542
TEST=Verified that autotests were still passing
CQ-DEPEND=CL:952036

Change-Id: I072a56faf78a3c453e9195e7a4f8cf5599872796
Reviewed-on: https://chromium-review.googlesource.com/954768
Reviewed-by: Wu-Cheng Li <wuchengli@chromium.org>
Commit-Queue: Alexandre Courbot <acourbot@chromium.org>
Cr-Commit-Position: refs/heads/master@{#543971}
1 file changed