Fix PR 28885: Fix AST Printer output for the inherited constructor using

declarations.

This commit ensures that the correct record type is printed out for the
using declarations that represent C++ inherited constructors.
It fixes a regression introduced in r274049 which changed the name that's
stored in the using declarations that correspond to inherited constructors.

Differential Revision: https://reviews.llvm.org/D25131

llvm-svn: 283102