Improve the lead diagnostic for C++ object subscript expressions with
no viable overloads.  Use a different message when the class provides
no operator[] overloads at all; use it for operator(), too.

Partially addresses PR 5900.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@92894 91177308-0d34-0410-b5e6-96231b3b80d8
4 files changed