One might think that it shouldn't be run because of 'if (declaration
!is KtNamedDeclaration) return' check in the 'check'-overload.
However, for default accessors we pass PSI for property, i.e.
KtProperty (see 'DeclarationCheckers.checkAccessors'), which
obviously passes this check
Note that we can't use `DescriptorToSourceUtils` here, because it's
returns `KtProperty` for default accessor too.
This commits adds specific check for that case, to avoid exception in
KT-28385. Ideal solution would be to either don't launch checkers on
such parameters, or explicitly declare semantic of the
'declaration'-parameter, e.g. to rename it to 'reportOn' (see KT-28403
for discussion)
^KT-28385 Fixed
Evgeniy.Zhelenskiy