[svn-r10816] Purpose: Fix bug (reported by user, not filed)

Description:
    Passing 0 where it should be "".  Fixed!

Platforms tested:
    Linux 2.4 (heping) - very minor, and has been in 1.6 for a while

c++/src/H5DataSet.cpp

@@ -92,7 +92,7 @@ hid_t DataSet::p_get_type() const
       return( type_id );
    else
    {
-      throw DataSetIException(0, "H5Dget_type failed");
+      throw DataSetIException("", "H5Dget_type failed");
    }
 }