Roll Skia from 8a6bdf14d215 to c21902c0d3cc (3 revisions)

https://skia.googlesource.com/skia.git/+log/8a6bdf14d215..c21902c0d3cc

2020-10-30 skia-autoroll@skia-public.iam.gserviceaccount.com Roll ANGLE from e3eaa60f1faf to 39b777c6f00f (20 revisions)
2020-10-30 skia-autoroll@skia-public.iam.gserviceaccount.com Roll Chromium from 6ce7ceff to 2357c735 (507 revisions)
2020-10-30 skia-autoroll@skia-public.iam.gserviceaccount.com Roll SwiftShader from 2be25f08deaf to e6c9497255c6 (3 revisions)

If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/skia-autoroll
Please CC jcgregorio@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-blink-rel;luci.chromium.try:linux-chromeos-compile-dbg;luci.chromium.try:linux_optional_gpu_tests_rel;luci.chromium.try:mac_optional_gpu_tests_rel;luci.chromium.try:win_optional_gpu_tests_rel
Cq-Do-Not-Cancel-Tryjobs: true
Bug: None
Tbr: jcgregorio@google.com
Test: Test: Test: Build on AOSP and launch CuttlefishTest: Test: VulkanMultithreadingTest::MultiContextDrawSmallDescriptorPools()
Change-Id: I6539bf235093cbb557f71da371bc3ba450bc93e7
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2509037Reviewed-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@{#822574}

DEPS

@@ -206,7 +206,7 @@ vars = {
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling Skia
   # and whatever else without interference from each other.
-  'skia_revision': '8a6bdf14d21534c5ef46401675c8cff8006976b5',
+  'skia_revision': 'c21902c0d3cc10cf13a8c5dfe9a610dc78e873ae',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling V8
   # and whatever else without interference from each other.