Roll ANGLE from 6b2639b023f9 to 84bd9dade9cb (6 revisions)

https://chromium.googlesource.com/angle/angle.git/+log/6b2639b023f9..84bd9dade9cb

2020-09-02 syoussefi@chromium.org Vulkan: Allow pbuffer usage if no window support
2020-09-02 geofflang@chromium.org Add a frontend feature to disable anisotropic filtering.
2020-09-02 syoussefi@chromium.org Vulkan: Don't break the RP on masked/scissored clears
2020-09-02 sugoi@google.com Make copyTexImage2D robust when source area is out of bounds
2020-09-02 syoussefi@chromium.org Vulkan: Fix resolve with different formats
2020-09-02 syoussefi@chromium.org Vulkan: Fix resolve-with-subpass with non-zero read attachment

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/+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:1034840,chromium:1123524
Tbr: cwallez@google.com
Change-Id: Icf79fe2ec8d251015215e21e800877538092f27c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2391373Reviewed-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@{#804006}

DEPS

@@ -207,7 +207,7 @@ 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': '6b2639b023f90759d6be3607186e9b71530f0a85',
+  'angle_revision': '84bd9dade9cb8b6275b4a285157d0201c9f340cc',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling SwiftShader
   # and whatever else without interference from each other.