Roll ANGLE from 957a2359f66b to 6c1581646c46 (7 revisions)

https://chromium.googlesource.com/angle/angle.git/+log/957a2359f66b..6c1581646c46

2020-06-02 jmadill@chromium.org Vulkan: Fix XFB invalid accesses in buffer OOM.
2020-06-02 amaiorano@google.com Fix copy subtexture to GL_RGB9_E5 in ANGLE/VK
2020-06-02 ynovikov@chromium.org Roll third_party/VK-GL-CTS/src/ 60972ed7f..80dc8399b (67 commits)
2020-06-02 m.maiya@samsung.com EGL: EGL_CreateSync validation bug fix
2020-06-02 cclao@google.com Vulkan: Add IMAGE_USE_STORAGE bit only if necessary.
2020-06-02 ianelliott@google.com Vulkan: Swap RenderArea coords for pre-rotation
2020-06-02 lehoangq@gmail.com Metal: refactor RenderUtils to split into multiple util classes.

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 ynovikov@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/+doc/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;luci.chromium.try:linux-swangle-try-x64;luci.chromium.try:win-swangle-try-x86
Bug: chromium:1086532
Tbr: ynovikov@google.com
Test: Test: angle_deqp_egl_no_gtest.exe --deqp-case=dEQP-EGL.functional.fence_sync.invalid.create_invalid_type
Change-Id: I343a8ec56cca202a9cd9240eacada8a47ca9f83f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2227683Reviewed-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@{#774517}

DEPS

@@ -194,7 +194,7 @@ 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': '957a2359f66ba6f61ca52104cc0a1338b16fd994',
+  'angle_revision': '6c1581646c4685c457bdc9381ede430e15253bef',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling SwiftShader
   # and whatever else without interference from each other.