Constrain __bind functor constructor such that it won't accidentally get used as a copy constructor from a non-const lvalue.  Fixes <rdar://problem/11359080>.

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@156182 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed