Correctly refer to element CVR qualifications when determining if a type is
more or less cv-qualified than another during implicit conversion and overload
resolution ([basic.type.qualifier] p5). Factors the logic out of template
deduction and into the ASTContext so it can be shared.

This fixes several aspects of PR5542, but not all of them.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@92248 91177308-0d34-0410-b5e6-96231b3b80d8
6 files changed