Roll src/third_party/dart 8b88946..02a8b01 (26 commits) (flutter#14278)

dart-lang/sdk@02a8b015ad Migrate corelib tests starting with "j" to "q" to NNBD.
dart-lang/sdk@617933c3c1 [vm, gc] As a debugging aid, remember the previous object during heap iteration.
dart-lang/sdk@964c9d8c20 [dart2js] new-rti: debug print of named type variable miss
dart-lang/sdk@7974f3f899 [dartdevc] Reduce the number of SDK libraries in the platform
dart-lang/sdk@b296d55c55 Issue 39709. Disable implicit 'call' tear-off for nullable objects.
dart-lang/sdk@ded753a397 Use 'isNonNullableByDefault' as the flag name everywhere.
dart-lang/sdk@86723cd5b1 Remove unused private methods and explicit 'new'.
dart-lang/sdk@108a80bd0d NNBD: Mark some good tests as passing; add FailingTests for some GitHub issues
dart-lang/sdk@2015c55277 [dartdevc] Remove ability to run analyzer based DDC
dart-lang/sdk@2a1fadb66c [dart2js] types_propagation - handle HAsCheckSimple
dart-lang/sdk@20ec71d447 [vm/compiler] Fix TypeTestingStub -> SubtypeTestCache fallback code if dst_type = TypeParameter
dart-lang/sdk@1aeff32c14 NNBD migrator: record type information in TypeName type arguments
dart-lang/sdk@a17884aff0 [vm] Fix late final local variables in AST mode
dart-lang/sdk@991e55f6ad NNBD Migrator: Fix generic super initializers
dart-lang/sdk@9605cca5a6 Make a method public that is overridden in a subclass
dart-lang/sdk@55f86c13cb [dartfuzz] Fix infinite recursion
dart-lang/sdk@de0e432ef1 Create an abstract layer to customize querying element types.
dart-lang/sdk@5f7177db84 Handle two non-operators as if they were operators to prevent a failure when assertions are enabled
dart-lang/sdk@22fef10a59 [nnbd_migration] suppress fewer upstream exact nullable nodes
dart-lang/sdk@b37f391f34 [VM/nnbd] Make runtimeType return a non-nullable type when the NNBD experiment is enabled.
dart-lang/sdk@bafd4e8dc6 Issue 39668. Use 'read type' to check dead '??='.
dart-lang/sdk@8894b88467 [VM/nnbd] Implement syntactic type equality.
dart-lang/sdk@cb94390c63 [infra] Improve efficiency of cloning the Flutter repositories
dart-lang/sdk@42799b66b6 Add support for unmanaged packages to trial_migration.
dart-lang/sdk@304eb2cb7b [test] Remove extra / in dartdevc nndb test suite runner.
dart-lang/sdk@16e7647c86 [ VM / dart:typed_data ] Fixed issue where null could be passed for simd types in AOT

Author: bkonyi

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': '8b8894648f0dbe53b046133caab11fbe8e14dc3f',
+  'dart_revision': '02a8b015ada14d556cc5683970d2ccab351b679c',
 
   # WARNING: DO NOT EDIT MANUALLY
   # The lines between blank lines above and below are generated by a script. See create_updated_flutter_deps.py

ci/licenses_golden/licenses_third_party

@@ -1,4 +1,4 @@
-Signature: 63d3e0cd0caf64c5b89692fc9f875051
+Signature: 387e5572f4d5397cd2535ecdfd59a341
 
 UNUSED LICENSES: