Roll Dart SDK from fe12b0536f42 to a188781c9fc8 (1 revision) (#22378)

https://dart.googlesource.com/sdk.git/+log/fe12b0536f42..a188781c9fc8

2020-11-06 dart-luci-ci-builder@dart-ci.iam.gserviceaccount.com Version 2.12.0-28.0.dev

If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/dart-sdk-flutter-engine
Please CC dart-vm-team@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

DEPS

@@ -34,7 +34,7 @@ vars = {
   # Dart is: https://github.com/dart-lang/sdk/blob/master/DEPS.
   # You can use //tools/dart/create_updated_flutter_deps.py to produce
   # updated revision list of existing dependencies.
-  'dart_revision': 'fe12b0536f42c0dc4e5fd436e6243b8440577438',
+  'dart_revision': 'a188781c9fc8ab950605716fb813bc5f2ca70e25',
 
   # WARNING: DO NOT EDIT MANUALLY
   # The lines between blank lines above and below are generated by a script. See create_updated_flutter_deps.py
@@ -50,7 +50,7 @@ vars = {
   'dart_linter_tag': '0.1.123',
   'dart_oauth2_tag': '1.6.0',
   'dart_protobuf_rev': '3746c8fd3f2b0147623a8e3db89c3ff4330de760',
-  'dart_pub_rev': '900e796a37fd9f68de9dd183cf4798fe5f055eaa',
+  'dart_pub_rev': '4ca4767a6c00b2dadecdaee9a4866dae40ef25f2',
   'dart_pub_semver_tag': 'v1.4.4',
   'dart_resource_rev': '6b79867d0becf5395e5819a75720963b8298e9a7',
   'dart_root_certificates_rev': '7e5ec82c99677a2e5b95ce296c4d68b0d3378ed8',

ci/licenses_golden/licenses_third_party

-Signature: 3073aca8c09fcf4aea4f22ece3f72438
+Signature: ad31226a4ca7a37ab610606d71887092
 
 UNUSED LICENSES: