For a method invocation temps might get allocated for both the receiver
and argument(s) so that:
A().foo(await null)
becomes:
Future<void> tmp0
...
tmp0 = A() // <- Type mismatch.
yield ...
tmp0 = tmp0.foo(:result) // <- Correct type.
This happens because the liveness analysis finds that the (previously
dynamic) temps can be reused.
Unfortunately 121988 added typing information to these temps, which
means they can't be simply reused in all cases.
This fix makes the temps dynamic again (by removing the type) but adds
unsafecasts to all VariableGets to propagate the know type.
Bug: https://github.com/flutter/flutter/issues/51828
Change-Id: I89c82763e0d4f8b102bb55dec3b694d017345517
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/138500
Reviewed-by: Johnni Winther <johnniwinther@google.com>
Commit-Queue: Clement Skau <cskau@google.com>
