Set origin when doing kind_of? comparisons

src/object.c

@@ -487,6 +487,7 @@ mrb_obj_is_kind_of(mrb_state *mrb, mrb_value obj, struct RClass *c)
       mrb_raise(mrb, E_TYPE_ERROR, "class or module required");
   }
 
+  c = c->origin;
   while (cl) {
     if (cl == c || cl->mt == c->mt)
       return TRUE;

test/t/module.rb

@@ -543,21 +543,21 @@ assert('Module#prepend') do
     b = labeled_module('b') { include a }
     c = labeled_module('c') { prepend b }
 
-    assert bug6654 do
+    #assert bug6654 do
       # the Module#< operator should be used here instead, but we don't have it
       assert_include(c.ancestors, a)
       assert_include(c.ancestors, b)
-    end
+    #end
 
     bug8357 = '[ruby-core:54736] [Bug #8357]'
     b = labeled_module('b') { prepend a }
     c = labeled_class('c') { include b }
 
-    assert bug8357 do
+    #assert bug8357 do
       # the Module#< operator should be used here instead, but we don't have it
       assert_include(c.ancestors, a)
       assert_include(c.ancestors, b)
-    end
+    #end
 
     bug8357 = '[ruby-core:54742] [Bug #8357]'
     assert_kind_of(b, c.new, bug8357)