[CP] Fix compiler crash when returning a value of uninitialized late variable from async function #50894
Description
Commit(s) to merge
Target
beta, stable
Prepared changelist for beta/stable
https://dart-review.googlesource.com/c/sdk/+/278362, https://dart-review.googlesource.com/c/sdk/+/278361
Issue Description
AOT compiler crashed on the Dart code which was returning a value of uninitialized late local variable from async function.
What is the fix
Internal classes (such as uninitialized sentinel) are properly handled when checking if return value of async function is a Future.
Why cherry-pick
Reported by user; this bug prevents building their Flutter app in profile/release modes.
Risk
low
Issue link(s)
Extra Info
No response