libide: allow accessing ide_object_set_context()

This should help bindings in some languages that want access to this
vfunc even though it shouldn't really be called.

libide/ide-object.c

@@ -111,7 +111,7 @@ ide_object_get_context (IdeObject *self)
   return priv->context;
 }
 
-static void
+void
 ide_object_set_context (IdeObject  *self,
                         IdeContext *context)
 {

libide/ide-object.h

@@ -37,6 +37,8 @@ struct _IdeObjectClass
 };
 
 IdeContext *ide_object_get_context (IdeObject            *self);
+void        ide_object_set_context (IdeObject            *self,
+                                    IdeContext           *context);
 void        ide_object_new_for_extension_async
                                    (GType                 interface_gtype,
                                     GCompareDataFunc      sort_priority_func,