[glibmm/private-export] class_shared.m4: Decorate private class prototype

[Chun-wei Fan <fanchunwei src gnome org>]

commit 4f736b294fd6fe437381cc2cb4a053f555b9724f
Author: Chun-wei Fan <fanchunwei src gnome org>
Date:   Fri Aug 28 12:07:22 2020 +0800

    class_shared.m4: Decorate private class prototype
    
    ...when using _WRAP_GOBJECT with a function decoration.  This will help expose
    the class definition in the generated private/*_p.h in the built DLLs/LIBs that
    is built with Visual Studio or clang-cl.

 tools/m4/class_shared.m4 | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/tools/m4/class_shared.m4 b/tools/m4/class_shared.m4
index 68804128..587a1f2f 100644
--- a/tools/m4/class_shared.m4
+++ b/tools/m4/class_shared.m4
@@ -101,7 +101,7 @@ dnl
 dnl
 dnl
 define(`_PH_CLASS_DECLARATION',`dnl
-class __CPPNAME__`'_Class : public Glib::Class
+class __FUNC_DECORATION__ __CPPNAME__`'_Class : public Glib::Class
 {
 public:
 #ifndef DOXYGEN_SHOULD_SKIP_THIS