[vm] Fix expression evaluation in context of closures

When evaluating an expressino at a breakpoint that's inside a closure,
the closure may refer to anything it closes over. That includes the
`this` from an enclosing method.

So depending on whether a closure's parent chain is an instance method
or a static method, the expression evaluation function is going to be an
instance method or a static method.

=> We walk up the parent chain to determine the correct enclosing class.
=> This avoids making a Type object with a cid from a top-level class (see [0])

Handling this correctly will now try to get the `this` when invoking an
eval function that has an enclosing instance method. Though we may often
have "<optimized out>" the `this` (e.g. due to not capturing it in
closure context chain).

=> We still allow running the expression evaluation function in this
case, but only if the expression being evaluated doesn't access `this`.

A similar issue occurs when trying to use variables in the eval
expression that the closure didn't capture. This results in a confusing
CFE compile-time error. This is a separate issue and tracked in [1].

=> We update the test to distinuish the cases that this CL makes passing
and those that are failing due to [1].

Fixes [0] https://github.com/dart-lang/sdk/issues/53061
See also [1] https://github.com/dart-lang/sdk/issues/53087

TEST=Fixes part of service/evaluate_activation_test failures

Change-Id: I3bb24e7338c7b2f12d5340311d944cb59a455641
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/317540
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Reviewed-by: Slava Egorov <vegorov@google.com>
Commit-Queue: Martin Kustermann <kustermann@google.com>
13 files changed
tree: a525360e2a5af71c60b7aee9766eb78b429c8b43
  1. .dart_tool/
  2. .github/
  3. benchmarks/
  4. build/
  5. docs/
  6. pkg/
  7. runtime/
  8. samples/
  9. sdk/
  10. tests/
  11. third_party/
  12. tools/
  13. utils/
  14. .clang-format
  15. .gitattributes
  16. .gitconfig
  17. .gitignore
  18. .gn
  19. .mailmap
  20. .style.yapf
  21. .vpython
  22. AUTHORS
  23. BUILD.gn
  24. CHANGELOG.md
  25. codereview.settings
  26. CONTRIBUTING.md
  27. DEPS
  28. LICENSE
  29. OWNERS
  30. PATENT_GRANT
  31. PRESUBMIT.py
  32. README.dart-sdk
  33. README.md
  34. sdk.code-workspace
  35. sdk_args.gni
  36. SECURITY.md
  37. WATCHLISTS
README.md

Dart

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