Roll Skia from 372791761157 to cc6961b9ac5e (7 revisions)

https://skia.googlesource.com/skia.git/+log/372791761157..cc6961b9ac5e

2021-01-22 johnstiles@google.com Add checkpointing functionality to SkSL Lexer.
2021-01-22 egdaniel@google.com Remove preferring cached memory for vulkan cpu write, gpu read memory.
2021-01-22 ethannicholas@google.com SkSL vars now track their declaration instead of their initial value
2021-01-22 brianosman@google.com SkSL: Remove ByteCode interpreter, generator, etc.
2021-01-22 bsalomon@google.com Revert "Revert "Reland "asyncRescaleAndRead supports unpremul results on GPU"""
2021-01-22 johnstiles@google.com Factor out modifier-token parsing into helper function.
2021-01-22 reed@google.com More hiding of legacy drawImage calls

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 scroggo@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: scroggo@google.com
Change-Id: If1a364c60712e3328fd0c3b1b50ba711419a8c40
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2645104Reviewed-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@{#846177}

DEPS

@@ -199,7 +199,7 @@ 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': '372791761157114400b92fd9a896d06814ef2a75',
+  'skia_revision': 'cc6961b9ac5e3ae7241ba5c625dd512476d7c7c6',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling V8
   # and whatever else without interference from each other.