store set of dispatch classes in built-in function objects * ov-fcn.h (octave_function::push_dispatch_class, octave_function::handles_dispatch_class): New virtual functions. * ov-builtin.h, ov-builtin.cc (octave_builtin::push_dispatch_class, octave_builtin::handles_dispatch_class): New functions. * symtab.h, symtab.cc (symbol_table::fcn_info::fcn_info_rep::install_built_in_dispatch): Define in .cc file. Store class names in built-in function object instead of class_methods. (symbol_table::fcn_info::fcn_info_rep::load_class_method): Also search for built-in functions that are declared to handle specific types.

--- a/libinterp/octave-value/ov-builtin.cc	Thu Dec 15 21:53:28 2016 -0500
+++ b/libinterp/octave-value/ov-builtin.cc	Thu Dec 15 22:04:11 2016 -0500
@@ -159,5 +159,17 @@
   return f;
 }
 
+void
+octave_builtin::push_dispatch_class (const std::string& dispatch_type)
+{
+  dispatch_classes.insert (dispatch_type);
+}
+
+bool
+octave_builtin::handles_dispatch_class (const std::string& dispatch_type) const
+{
+  return dispatch_classes.find (dispatch_type) != dispatch_classes.end ();
+}
+
 const std::list<octave_lvalue> *octave_builtin::curr_lvalue_list = 0;