Roll Skia from f2efb80bc316 to 420a9ba7b5e9 (4 revisions)

https://skia.googlesource.com/skia.git/+log/f2efb80bc316..420a9ba7b5e9

2020-11-25 reed@google.com Switch to m44 for the rest of canvas virtuals
2020-11-25 mtklein@google.com remove SkVM uniform8/16
2020-11-25 mtklein@google.com remove SkVM Q14 support
2020-11-25 mtklein@google.com clean up unused SkVM debug features

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 michaelludwig@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: michaelludwig@google.com
Change-Id: Ife9b9ae4101b80045c3b7578a36d65ebf38c78c0
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2560814Reviewed-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@{#831185}

DEPS

@@ -200,7 +200,7 @@ 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': 'f2efb80bc3166c334b6b0e01283eba4fd0c89f41',
+  'skia_revision': '420a9ba7b5e99a3a6d539190cbff4198d1ee9e7e',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling V8
   # and whatever else without interference from each other.