viz: Remove TestWebGraphicsContext3D in Layer*Test-Step 1a

BUG=837155

Cq-Include-Trybots: luci.chromium.try:android_optional_gpu_tests_rel;master.tryserver.blink:linux_trusty_blink_rel
Change-Id: I51327a0a0fcd8f23050ccc214f0169e8b6740e6d
Reviewed-on: https://chromium-review.googlesource.com/1051262
Reviewed-by: danakj <danakj@chromium.org>
Commit-Queue: Xing Xu <xing.xu@intel.com>
Cr-Commit-Position: refs/heads/master@{#559360}
14 files changed