Roll Skia from dc75a97b8010 to c4fbc8d6cf34 (3 revisions)

https://skia.googlesource.com/skia.git/+log/dc75a97b8010..c4fbc8d6cf34

2020-11-30 robertphillips@google.com Stop overflow of windows rects in GrClipStack
2020-11-30 johnstiles@google.com Fix SPIR-V and Metal support for enum types.
2020-11-30 johnstiles@google.com Fix SPIR-V compilation error with arrays of samplers.

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
Change-Id: I7b0d288842aeefc977b942d0db79ad94468332c6
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2565106Reviewed-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@{#831950}

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': 'dc75a97b80100e4f70852548409df410665974a9',
+  'skia_revision': 'c4fbc8d6cf34224d98c0e03a263c826d0d176b4e',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling V8
   # and whatever else without interference from each other.