Explanation: We did not have support to generate swiftified overload for
initializers. This PR adds that support.
Issue: rdar://152112660
Risk: Low, the feature is localized to swiftified overloads.
Testing: Regression test added.
Original PR: #81947
Reviewer: @hnrklssn
Lookup into C++ namespaces uses a different path from C++ record declarations.
Augment the C++ namespace lookup path to also account for the auxiliary
declarations introduced by peer macro expansions.
When performing name lookup into a C++ record type, make sure that we
also walk through auxiliary declarations (i.e., declarations that can
come from peer macro expansions) to find results.
Fixes rdar://146833294.
