Replace the code that parses member access expressions after "." or

"->" with a use of ParseUnqualifiedId. Collapse
ActOnMemberReferenceExpr, ActOnDestructorReferenceExpr (both of them),
ActOnOverloadedOperatorReferenceExpr,
ActOnConversionOperatorReferenceExpr, and
ActOnMemberTemplateIdReferenceExpr into a single, new action
ActOnMemberAccessExpr that does the same thing more cleanly (and can
keep more source-location information).

llvm-svn: 85930