Roll Skia from be1455850c3c to 8bd6c9830dd4 (7 revisions)

https://skia.googlesource.com/skia.git/+log/be1455850c3c..8bd6c9830dd4

2020-08-21 bungeman@google.com Fixup fontmgr_bounds gm for variable fonts
2020-08-21 csmartdalton@google.com Reland "Add utilities to SkGeometry for quad and cubic rotation angles"
2020-08-21 johnstiles@google.com Add missing headers to .gn files.
2020-08-21 bsalomon@google.com Fix -Wstring-concatenation warnings in clang 12
2020-08-21 bsalomon@google.com Test performance of ANGLE ES3 on nanobench bots.
2020-08-21 egdaniel@google.com Add image usage flags to GrVkImageInfo
2020-08-21 brianosman@google.com Fix two null dereference bugs in SkSL visitor

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 stani@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: stani@google.com
Change-Id: I6e2f52f03ac3817b66dd686d7582f7bc783564f1
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2368185Reviewed-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@{#800712}

DEPS

@@ -195,7 +195,7 @@ 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': 'be1455850c3cb9da0217c7d7f6413b94654eef74',
+  'skia_revision': '8bd6c9830dd4b9192dc2ee951afeb00687caaa03',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling V8
   # and whatever else without interference from each other.