[libsigc++2/variadic_bind4] functor_trait.h: Do not repeat mem_functor and pointer_function declarations.

[Murray Cumming <murrayc src gnome org>]

commit 522960bf18749176043ecd5c924202c9ef18a50c
Author: Murray Cumming <murrayc murrayc com>
Date:   Fri Mar 4 11:20:54 2016 +0100

    functor_trait.h: Do not repeat mem_functor and pointer_function declarations.
    
    Instead just include the headers.
    Then we can change their declarations without having to do it in two places.

 sigc++/functors/functor_trait.h |    9 ++-------
 1 files changed, 2 insertions(+), 7 deletions(-)
---
diff --git a/sigc++/functors/functor_trait.h b/sigc++/functors/functor_trait.h
index f02ff39..62dc9e6 100644
--- a/sigc++/functors/functor_trait.h
+++ b/sigc++/functors/functor_trait.h
@@ -1,6 +1,8 @@
 #ifndef _SIGC_FUNCTORS_FUNCTOR_TRAIT_H_
 #define _SIGC_FUNCTORS_FUNCTOR_TRAIT_H_
 #include <sigc++/functors/functor_base.h>
+#include <sigc++/functors/mem_fun.h>
+#include <sigc++/functors/ptr_fun.h>
 #include <sigc++/type_traits.h>
 #include <type_traits>
 
@@ -190,10 +192,6 @@ struct functor_trait<T_functor, false, true>   \
 #ifndef DOXYGEN_SHOULD_SKIP_THIS
 // detect the return type and the functor version of non-functor types.
 
-template <class T_return, class... T_args>
-class pointer_functor;
-
-
 //functor ptr fun:
 
 template <class T_return, class... T_arg>
@@ -206,9 +204,6 @@ struct functor_trait<T_return (*)(T_arg...), false, false>
 
 //functor mem fun:
 
-template <class T_return, class T_obj, class... T_arg> class mem_functor;
-template <class T_return, class T_obj, class... T_arg> class const_mem_functor;
-
 template <class T_return, class T_obj, class... T_arg>
 struct functor_trait<T_return (T_obj::*)(T_arg...), false, false>
 {