Roll src/third_party/angle 47e3be4efd27..50a47bd99229 (3 commits)

https://chromium.googlesource.com/angle/angle.git/+log/47e3be4efd27..50a47bd99229

git log 47e3be4efd27..50a47bd99229 --date=short --first-parent --format='%ad %ae %s'
2020-03-30 angle-autoroll@skia-public.iam.gserviceaccount.com Roll third_party/vulkan-validation-layers/src 55f01953d6e9..9a0f2d99fd5d (4 commits)
2020-03-30 angle-autoroll@skia-public.iam.gserviceaccount.com Roll third_party/SwiftShader 02e15b249b12..1c29477aa06e (19 commits)
2020-03-30 angle-autoroll@skia-public.iam.gserviceaccount.com Roll third_party/vulkan-loader/src cc481ef27631..b0c27ce32864 (2 commits)

Created with:
  gclient setdep -r src/third_party/angle@50a47bd99229

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@google.com 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-asan;luci.chromium.try:win_optional_gpu_tests_rel
Bug: None
Tbr: cwallez@google.com
Change-Id: I7030f1176bc428a313c07aaababa6310f381b883
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2127126Reviewed-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@{#754465}

DEPS

@@ -187,7 +187,7 @@ 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': '47e3be4efd2780d424e3582457722628a9b07880',
+  'angle_revision': '50a47bd992294216b0fe08db02bdd78746b56d8e',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling SwiftShader
   # and whatever else without interference from each other.