Improve overloaded function handling in the typo correction code.

Change TypoCorrection to store a set of NamedDecls instead of a single
NamedDecl. Also add initial support for performing function overload
resolution to Sema::DiagnoseEmptyLookup.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@136807 91177308-0d34-0410-b5e6-96231b3b80d8
7 files changed