Roll Skia from 821a84558bd4 to 87a055b02027 (4 revisions) (#23825)

https://skia.googlesource.com/skia.git/+log/821a84558bd4..87a055b02027

2021-01-21 [email protected] Roll ANGLE from 382f016dd3b6 to f0286e636456 (15 revisions)
2021-01-21 [email protected] Roll Chromium from 78d95924cc6a to dac687f4cbf2 (517 revisions)
2021-01-21 [email protected] Roll Dawn from 311a17a8feae to 762814bd9229 (7 revisions)
2021-01-21 [email protected] Roll SwiftShader from 89fd1480b47e to b3e5c440d239 (5 revisions)

If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/skia-flutter-autoroll
Please CC [email protected] 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

Author: skia-flutter-autoroll

DEPS

@@ -27,7 +27,7 @@ vars = {
   'skia_git': 'https://skia.googlesource.com',
   # OCMock is for testing only so there is no google clone
   'ocmock_git': 'https://github.com/erikdoe/ocmock.git',
-  'skia_revision': '821a84558bd40fe0c73ed0c15a400372bbbbe51d',
+  'skia_revision': '87a055b02027f07e86fae81798c8274c31584c2d',
 
   # When updating the Dart revision, ensure that all entries that are
   # dependencies of Dart are also updated to match the entries in the

ci/licenses_golden/licenses_skia

@@ -1,4 +1,4 @@
-Signature: c2a40579caa23ef80ce17b61af39ff05
+Signature: d03f204019fb2896f7f46e6e06b959f8
 
 UNUSED LICENSES: