Make CXXBaseSpecifier::getType return unqual type.

Various pieces of code, like base initialization in Sema and RTTI IRGen,
don't properly ignore qualifiers on base classes.  Instead of auditing the
whole codebase, just strip them off in the getter.  (The type as written is
still available in the TypeSourceInfo for code that cares.)

Fixes PR16596.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@186125 91177308-0d34-0410-b5e6-96231b3b80d8
Provide a fixit hint for changing '->' to '.' if there is no operator->
defined for a class.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@186128 91177308-0d34-0410-b5e6-96231b3b80d8