Roll src/third_party/skia d04ddcd6c518..4ef1ca1d089e (4 commits)

https://skia.googlesource.com/skia.git/+log/d04ddcd6c518..4ef1ca1d089e

git log d04ddcd6c518..4ef1ca1d089e --date=short --first-parent --format='%ad %ae %s'
2019-12-19 michaelludwig@google.com Fix int/uint comparison in TextureOp asserts
2019-12-19 robertphillips@google.com Add glue to link the GrContext createCompressedBackendTexture API to the GL and Vulkan backends
2019-12-19 jvanverth@google.com Clean up GenDistanceFieldFromPath.
2019-12-19 halcanary@google.com public.bzl:  add SKOTTIE_IOS_LIB_{SRCS,HDRS}

Created with:
  gclient setdep -r src/third_party/skia@4ef1ca1d089e

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 borenet@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/+/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
Bug: None
Tbr: borenet@google.com
Change-Id: Ia709854bc94447f47a54ebbc58abe10e254ec567
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1976106Reviewed-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@{#726436}

DEPS

@@ -175,7 +175,7 @@ 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': 'd04ddcd6c5183208ff0837e7a30acf26356724ae',
+  'skia_revision': '4ef1ca1d089e909c8d62a36ea6f604696e784094',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling V8
   # and whatever else without interference from each other.