Use getNameAsString instead of getName to get method names when dumping

overrides:  getName can fail if the decl's name isn't a simple identifier.

This is a more general replacement for the fix in r305860.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@307959 91177308-0d34-0410-b5e6-96231b3b80d8