swift

467f8f5e - [Macros] Ensure that we can find peer macros for members of extensions.

[Macros] Ensure that we can find peer macros for members of extensions. When populating the name lookup tables for a nominal type, we were only visiting declarations with peer macros within the nominal type declaration itself. Also visit the members of extensions of the nominal type. Without this change, peer-macro-defined members of extensions are not visible.