5637: SSR: Matching trait associated constants, types and functions r=matklad a=davidlattimore
This fixes matching of things like `HashMap::default()` by resolving `HashMap` instead of `default` (which resolves to `Default::default`).
Same for associated constants and types that are part of a trait implementation.
However, we still don't support matching calls to trait methods.
Co-authored-by: David Lattimore <dml@google.com>