Roll src/third_party/skia 28a9b122f5a5..f68213fc4db3 (4 commits)

https://skia.googlesource.com/skia.git/+log/28a9b122f5a5..f68213fc4db3

git log 28a9b122f5a5..f68213fc4db3 --date=short --first-parent --format='%ad %ae %s'
2020-01-27 mtklein@google.com draw whole grid
2020-01-27 fmalita@chromium.org [skottie] Cleanup: convert transform adapters to new pattern
2020-01-27 mtklein@google.com rm mtklein@chromium
2020-01-27 bsalomon@google.com Revert "Switch runtime SkSL to always sample at explicit coords"

Created with:
  gclient setdep -r src/third_party/skia@f68213fc4db3

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 reed@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: reed@google.com
Change-Id: I8d9eac778e230ed8595651b91226526566dd42d3
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2023429Reviewed-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@{#735529}

DEPS

@@ -181,7 +181,7 @@ 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': '28a9b122f5a5331a15653bb60fb525e8d2ac82f4',
+  'skia_revision': 'f68213fc4db35db5389040113c77111fa3ff6aa2',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling V8
   # and whatever else without interference from each other.