Required method apply< forward > in BlockPreconditioner not present in preconditioner interface.

I came across the following issue. In BlockPreconditioner (schwarz.hh line 334 ff.) a method

template<bool forward>
void apply (X& v, const Y& d)
{
  _preconditioner->template apply<forward>(v,d);
  _communication.copyOwnerToAll(v,v);
}

is implemented but the corresponding method on the Preconditioner interface class is missing. Strange that this occurs now.