Try turning object-observe test back on in gc-stress

test/mjsunit/mjsunit.status

 # Copyright 2012 the V8 project authors. All rights reserved.
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 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
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@@ skipping 291 matching lines @@
   'compiler/osr-regress-max-locals': [PASS, NO_VARIANTS],
   'math-floor-of-div': [PASS, NO_VARIANTS],
   'unicodelctest': [PASS, NO_VARIANTS],
   'unicodelctest-no-optimization': [PASS, NO_VARIANTS],
 
   # Too slow for gc stress.
   'asm/embenchen/box2d': [SKIP],
 
   # Issue 3723.
   'regress/regress-3717': [SKIP],
-  # Issue 478788.
-  'es7/object-observe': [SKIP],
 
   # BUG(v8:4237)
   'regress/regress-3976': [SKIP],
 
   # BUG(v8:4359)
   'strong/load-proxy': [SKIP],
 }],  # 'gc_stress == True'
 
 ##############################################################################
 ['byteorder == big', {
@@ skipping 327 matching lines @@
   'harmony/symbols': [SKIP],
 }],  # 'arch == nacl_ia32 or arch == nacl_x64'
 
 ##############################################################################
 ['deopt_fuzzer == True', {
 
   # Skip tests that are not suitable for deoptimization fuzzing.
   'assert-opt-and-deopt': [SKIP],
   'never-optimize': [SKIP],
   'regress/regress-2185-2': [SKIP],
-  'harmony/object-observe': [SKIP],
   'readonly': [SKIP],
   'array-feedback': [SKIP],
 
   # Deopting uses just enough memory to make this one OOM.
   'regress/regress-3976': [SKIP],
 
   # Deopt every n garbage collections collides with deopt every n times.
   'regress/regress-2653': [SKIP],
 }],  # 'deopt_fuzzer == True'
 
 ##############################################################################
 ['arch == ppc and simulator_run == True or arch == ppc64 and simulator_run == True', {
 
   # take too long with the simulator.
   'regress/regress-1132': [SKIP],
 }],  # 'arch == ppc and simulator_run == True'
 ]