Roll src/third_party/dart 98c13ba..c74a8ec (14 commits) (flutter#14309)

dart-lang/sdk@c74a8ec2c4 [vm/bytecode] Fix handling of contravariant parameters in isUncheckedCall
dart-lang/sdk@4ce13659b4 Update server API to allow URLs to be returned to dartfix
dart-lang/sdk@e22ddd1372 Update TypeSystemTest to reuse more ElementsTypesMixin.
dart-lang/sdk@e1ef70fad4 [vm] Add nnbd-experiment to the snapshot feature string
dart-lang/sdk@ec6e8c8dfa Clarify the roles of isolate_data and isolate_group_data in Dart_CreateIsolateGroup
dart-lang/sdk@b69596bb1b [vm/compiler] Dead code elimination
dart-lang/sdk@1cc5d6927a Deprecate ErrorReporter.reportTypeErrorForNode()
dart-lang/sdk@28b0f18397 Add basic git package management to trial_migration.
dart-lang/sdk@25def20f5d Revert "[infra] Add failing test to test CI systems and approvals workflow"
dart-lang/sdk@620dd7dab5 Use just DartType.getDisplayString() in ErrorReporter.
dart-lang/sdk@d03a7686d2 [vm/compiler] Fix inlining of SIMD shuffle operations
dart-lang/sdk@6a16a59d08 Additional fixes to analyzer pubspec.
dart-lang/sdk@bb8bece3bf Widen the analyzer's pubspec constraint on _fe_analyzer_shared
dart-lang/sdk@e578eeb235 [infra] Add failing test to test CI systems and approvals workflow

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': '98c13ba18f42b2efd3b9330ee05e1ddad08d816c',
+  'dart_revision': 'c74a8ec2c46e71491ae6ff3449b2997a6093bea5',
 
   # 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: 11786b18ee722ed30adc6af4a31201a6
+Signature: 14461554cb71cf23106c5f39a3431fd0
 
 UNUSED LICENSES: