Roll Skia from 7b1620f36648 to db4a9fbc6532 (10 revisions)

https://skia.googlesource.com/skia.git/+log/7b1620f36648..db4a9fbc6532

2020-09-16 herb@google.com verify there are no glyph searches
2020-09-16 michaelludwig@google.com Reland "Enable novel GrClipStack on bots, disable elsewhere"
2020-09-16 brianosman@google.com Remove swizzle helper function for type creation
2020-09-16 johnstiles@google.com Avoid redundant zeros and ones in swizzle constructor.
2020-09-16 herb@google.com simplify setMetricsAndImage API
2020-09-16 adlai@google.com Remove SkSurface::getContext
2020-09-16 michaelludwig@google.com Use SkClipOp::kIntersect instead of kReplace_ClipOp
2020-09-16 ethannicholas@google.com Revert "moved BinaryExpression's data into IRNode"
2020-09-16 johnstiles@google.com Migrate swizzle tests to golden SkSL files.
2020-09-16 mtklein@google.com good codegen for Op::mul_q14x2

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 scroggo@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: scroggo@google.com
Change-Id: Ifd83997383a14f396f554a0b0e38280c28b8acf7
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2415021Reviewed-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@{#807680}

DEPS

@@ -195,7 +195,7 @@ 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': '7b1620f36648c8c31a2e03dc4f5df18e6a9c700b',
+  'skia_revision': 'db4a9fbc65321c666a9507fdfec64b044ad76ea8',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling V8
   # and whatever else without interference from each other.