Serializer: correctly deal with internal references.

test/mjsunit/mjsunit.status

 # Copyright 2012 the V8 project authors. All rights reserved.
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 #       notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 #       copyright notice, this list of conditions and the following
 #       disclaimer in the documentation and/or other materials provided
@@ skipping 83 matching lines @@
   'debug-evaluate-const': [PASS, NO_VARIANTS],
   'debug-evaluate-locals': [PASS, NO_VARIANTS],
   'debug-liveedit-check-stack': [PASS, NO_VARIANTS],  # only in no-snap mode.
   'debug-liveedit-double-call': [PASS, NO_VARIANTS],
   'debug-step-stub-callfunction': [PASS, NO_VARIANTS],
   'debug-set-variable-value': [PASS, NO_VARIANTS],
   'debug-stepin-accessor': [PASS, NO_VARIANTS],
   'debug-stepin-builtin': [PASS, NO_VARIANTS],
   'debug-stepin-constructor': [PASS, NO_VARIANTS],
   'debug-stepin-function-call': [PASS, NO_VARIANTS],
+  'debug-stepin-positions': [PASS, NO_VARIANTS],
+  'debug-stepin-property-function-call': [PASS, NO_VARIANTS],
   'debug-stepnext-do-while': [PASS, NO_VARIANTS],
   'debug-stepout-scope-part1': [PASS, NO_VARIANTS],
   'debug-stepout-scope-part2': [PASS, NO_VARIANTS],
   'debug-stepout-scope-part3': [PASS, NO_VARIANTS],
   'es6/debug-stepin-microtasks': [PASS, NO_VARIANTS],
   'es6/debug-stepnext-for': [PASS, NO_VARIANTS],
   'harmony/debug-evaluate-blockscopes': [PASS, NO_VARIANTS],
   'regress/regress-crbug-259300': [PASS, NO_VARIANTS],
 
   ##############################################################################
@@ skipping 474 matching lines @@
 ['arch == ppc and simulator_run == True or arch == ppc64 and simulator_run == True', {
 
   # take too long with the simulator.
   'regress/regress-1132': [SKIP],
   'asm/embenchen/box2d': [SKIP],
 
   # issues to be investigate4d
   'es6/collections': [SKIP],
 }],  # 'arch == ppc and simulator_run == True'
 ]