Make change to CompileSetup backwards compatible.

The c7f435026ff8591085f427b8ee4d192e1f10f783 introduced a new parameter
to the constructor of `CompileSetup` but it turns out that this class
is being used in zinc. Introduce an overloaded variant of that constructor
that preserves backwards compatibility.
Merge pull request #1125 from gkossakowski/compile-setup-nameHashing

Make change to CompileSetup backwards compatible.