Roll Skia from bcd1fc030a2b to a670782ed315 (5 revisions)

https://skia.googlesource.com/skia.git/+log/bcd1fc030a2b..a670782ed315

2020-10-19 egdaniel@google.com Update GrAttachment budgeted and gpu memory size calculation.
2020-10-19 csmartdalton@google.com Remove a redundant position assignment from stroke tessellation shaders
2020-10-19 egdaniel@google.com Implement computeScratchKey virtual for GrAttachment.
2020-10-19 brianosman@google.com Directly compute call counts, rather than mutating state
2020-10-19 bsalomon@google.com Revert "Revert "New variant of SkImage::MakeFromYUVATextures.""

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 egdaniel@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: egdaniel@google.com
Change-Id: I70238ada6f0b6210ad5db9a77f47c3b88c58fc1b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2485607Reviewed-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@{#818645}

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': 'bcd1fc030a2bf7e3a731ac6c24a8bfd2b84ec3fd',
+  'skia_revision': 'a670782ed315e81862d94aed6e3958e35cdc8f94',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling V8
   # and whatever else without interference from each other.