Revert "[cfe] Use `void` for let-expressions for extension property set"

This reverts commit a5fda592195b0bc42cadf1669df04502912c053c.

Reason for revert: breaks calling extension setters with `?.`, see b/241059207

Original change's description:
> [cfe] Use `void` for let-expressions for extension property set
> This pipes the expression type for a generated property setter, such
> that synthesized variables in let expressions created for the generated
> setter expression are typed correctly.
> Before this change a let variable created for an extension property set
> would use the value type even though the extension property setter is
> method with a void return type.
> Change-Id: I1e7d31eaf1410bb06d55e2845403865e0c7af452
> Reviewed-on:
> Commit-Queue: Johnni Winther <>
> Reviewed-by: Aske Simon Christensen <>,

Change-Id: Iaafd12833939cbd38e09787fcdb5a4c78a964656
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-by: Johnni Winther <>
Commit-Queue: Ilya Yanok <>
Reviewed-by: Ilya Yanok <>
80 files changed
tree: e4e05bfa28f498dc53a3860562220321dded479c
  1. .dart_tool/
  2. .github/
  3. benchmarks/
  4. build/
  5. docs/
  6. pkg/
  7. runtime/
  8. samples/
  9. samples-dev/
  10. samples_2/
  11. sdk/
  12. tests/
  13. third_party/
  14. tools/
  15. utils/
  16. .clang-format
  17. .gitattributes
  18. .gitconfig
  19. .gitignore
  20. .gn
  21. .mailmap
  22. .style.yapf
  23. .vpython
  27. codereview.settings
  29. DEPS
  31. OWNERS
  34. README.dart-sdk
  36. sdk_args.gni


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