Roll src/third_party/skia b7c5bac9da28..20c626aa2358 (2 commits)

https://skia.googlesource.com/skia.git/+log/b7c5bac9da28..20c626aa2358

git log b7c5bac9da28..20c626aa2358 --date=short --no-merges --format='%ad %ae %s'
2019-10-15 senorblanco@chromium.org Update Dawn backend to ToT.  This is about 3 months of changes.
2019-10-15 egdaniel@google.com Remove use of GrColorType as in param in SimpleTextureEffect.fp to just constructor param.

Created with:
  gclient setdep -r src/third_party/skia@20c626aa2358

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 csmartdalton@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
TBR=csmartdalton@google.com

Bug: None
Change-Id: I35d7bfb335459364bfa5fa9fc8cf29e9b3283cde
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1862270Reviewed-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@{#706234}

DEPS

@@ -167,7 +167,7 @@ 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': 'b7c5bac9da28a2a08b2f260bf467359ed075b583',
+  'skia_revision': '20c626aa2358d15d4840189607fbac9d52033701',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling V8
   # and whatever else without interference from each other.