Roll src/third_party/angle 93bb092f88c9..791ad7b8774a (2 commits)

https://chromium.googlesource.com/angle/angle.git/+log/93bb092f88c9..791ad7b8774a

git log 93bb092f88c9..791ad7b8774a --date=short --no-merges --format='%ad %ae %s'
2019-08-31 syoussefi@chromium.org Vulkan: Enable more GLES3.1 dEQP tests
2019-08-31 syoussefi@chromium.org Vulkan: Storage image support

Created with:
  gclient setdep -r src/third_party/angle@791ad7b8774a

If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/angle-chromium-autoroll
Please CC cwallez@chromium.org on the revert to ensure that a human
is aware of the problem.

To report a problem with the AutoRoller itself, please file a bug:
https://bugs.chromium.org/p/skia/issues/entry?template=Autoroller+Bug

Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+/master/autoroll/README.md

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
TBR=cwallez@chromium.org

Bug: None
Change-Id: I224c7e2a76bc7eb8c5f9d59c4cfb0a95168fed80
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1779496Reviewed-by: chromium-autoroll <chromium-autoroll@skia-public.iam.gserviceaccount.com>
Commit-Queue: chromium-autoroll <chromium-autoroll@skia-public.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/master@{#692368}

DEPS

@@ -174,7 +174,7 @@ vars = {
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling ANGLE
   # and whatever else without interference from each other.
-  'angle_revision': '93bb092f88c982ef4c6d4e0db72afc5d7c178b42',
+  'angle_revision': '791ad7b8774a06c996467eb9e6e5137b1e4ef452',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling SwiftShader
   # and whatever else without interference from each other.