Roll Skia from 986c7fb8caea to 51c01588f31e (3 revisions)

https://skia.googlesource.com/skia.git/+log/986c7fb8caea..51c01588f31e

2020-12-01 mtklein@google.com add CPU feature detection for iOS / ARM Mac
2020-12-01 bsalomon@google.com Don't drop mip map mode in GrTextureOp->GrTextureEffect fallback
2020-12-01 skia-autoroll@skia-public.iam.gserviceaccount.com Roll ANGLE from 59aa1ef1975a to 234fccfb1818 (18 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 westont@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: westont@google.com
Test: Test: Test: FramebufferObjectTest*
Change-Id: I52b5e16a7c8185cc4b6e32a52b7681788929d86c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2568641Reviewed-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@{#832625}

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': '986c7fb8caea0cace5634c46d89324ea8ac2a58a',
+  'skia_revision': '51c01588f31ef0a1679b8d6fec19b39578c909b4',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling V8
   # and whatever else without interference from each other.