Roll Dart SDK from 1db2d4d95562 to 82b4c77fb17f (2 revisions) (#23861)

https://dart.googlesource.com/sdk.git/+log/1db2d4d95562..82b4c77fb17f

2021-01-22 [email protected] Version 2.12.0-253.0.dev
2021-01-22 [email protected] Version 2.12.0-252.0.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 [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

@@ -35,7 +35,7 @@ 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': '1db2d4d9556296482a207f171b4d732dcd8e2432',
+  'dart_revision': '82b4c77fb17fc1086bb2bc71ab63571494f0fcd6',
 
   # 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': '0.1.129',
   'dart_oauth2_tag': '1.6.0',
   'dart_protobuf_rev': '0d03fd588df69e9863e2a2efc0059dee8f18d5b2',
-  'dart_pub_rev': '392a3cb455af48f7ce8807a96174691945f97f0a',
+  'dart_pub_rev': '7cff05f2522d5468648f854695ca8671aae2104d',
   'dart_resource_rev': '6b79867d0becf5395e5819a75720963b8298e9a7',
   'dart_root_certificates_rev': '7e5ec82c99677a2e5b95ce296c4d68b0d3378ed8',
   'dart_shelf_packages_handler_tag': '2.0.0',
@@ -194,7 +194,7 @@ deps = {
    Var('dart_git') + '/dartdoc.git@9e61a4f11091aaa8998525a2692b14148dc24ab5',
 
   'src/third_party/dart/third_party/pkg/ffi':
-   Var('dart_git') + '/ffi.git@31352979f261f7c6ea88fa0a2cfb0fdd004c38fb',
+   Var('dart_git') + '/ffi.git@f288e906c92e2ab378768dfa61a40814ede7a2a5',
 
   'src/third_party/dart/third_party/pkg/file':
    Var('dart_git') + '/external/github.com/google/file.dart/@0e09370f581ab6388d46fda4cdab66638c0171a1',

ci/licenses_golden/licenses_third_party

@@ -1,4 +1,4 @@
-Signature: 2ee89baba494eb7e60d8cc39e16c8f41
+Signature: 3497a3a10f2939f3e38258b8d4ba165e
 
 UNUSED LICENSES: