When we're updating the subprogram scope DIE, we want to determine if we're

updating an abstract DIE or not. If we are, then we use that. Its children will
be added on later, as well as the object pointer attribute. Otherwise, this
function may be called with a concrete DIE twice and adding the children and
object pointer attribute to it twice.
<rdar://problem/12401423&12600340>

llvm-svn: 167524