NNBDMode does not reflect the semantics (legacy or nnbd) of type tests anymore.
Instead, the semantics are derived from the value of the strong mode flag.
This required one function to be specialized, namely the implementation of
'null is Type' in weak mode in an opted-in library, which still requires
nnbd semantics although run in weak mode.
Relevant changes are in object.h and object.cc:
- methods NNBD_NullIsInstanceOf and NNBD_IsTopType are new.
- methods IsNullType, IsTopType, and IsNeverType are modified.
Change-Id: I36cd43d93d2cfabd110cbcc6b26487a583bb089d
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/130444
Commit-Queue: Régis Crelier <regis@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Régis Crelier
e2e290b4cf