ParseCXXSimpleTypeSpecifier can only be called on things that are

verified to be simple type specifiers, so there is no need for it
to call TryAnnotateTypeOrScopeToken.

Make MaybeParseCXXScopeSpecifier reject ::new and ::delete with a 
hard error now that it may never be transitively called in a 
context where these are legal.  This allows me to start 
disentangling things more.

llvm-svn: 61659