Unlike in Swift, Obj-C allows method overrides to be declared in extensions
(categories), even outside of the module that defines the type that is being
extended. When MemberImportVisibility is enabled, these overrides must be
filtered out to prevent them from hijacking name lookup and causing the
compiler to insist that the module that defines the extension be imported.
Resolves rdar://145329988.
Unlike in Swift, Obj-C allows method overrides to be declared in extensions
(categories), even outside of the module that defines the type that is being
extended. When MemberImportVisibility is enabled, these overrides must be
filtered out to prevent them from hijacking name lookup and causing the
compiler to insist that the module that defines the extension be imported.
Resolves rdar://145329988.
