Roll Dart SDK from 1c14e29 to 5ae74b9 (1 revision)

https://dart.googlesource.com/sdk.git/+log/1c14e29fbfba..5ae74b9c13b0

2021-05-21 [email protected] Version 2.14.0-140.0.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.

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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': '1c14e29fbfbafa54f3d94d7839098a66e98c38b7',
+  'dart_revision': '5ae74b9c13b0aefba6286049105b150dfec8b3bc',
 
   # WARNING: DO NOT EDIT MANUALLY
   # The lines between blank lines above and below are generated by a script. See create_updated_flutter_deps.py