Blacklist tests due to optimizing toplevel with --always-opt.

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
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 #     * Redistributions in binary form must reproduce the above
 #       copyright notice, this list of conditions and the following
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@@ skipping 88 matching lines @@
   'debug-compile-event-newfunction': [PASS, NO_VARIANTS],
   'debug-conditional-breakpoints': [PASS, NO_VARIANTS],
   'debug-evaluate-locals-optimized': [PASS, NO_VARIANTS],
   'debug-evaluate-locals-optimized-double': [PASS, NO_VARIANTS],
   'debug-evaluate-recursive': [PASS, NO_VARIANTS],  # only in no-snap debug.
   'debug-step': [PASS, NO_VARIANTS],  # windows only.
   'debug-step-2': [PASS, NO_VARIANTS],  # flaky in no-snap mode.
   'debug-step-3': [PASS, NO_VARIANTS],  # flaky in no-snap mode.
   'debug-stepframe-clearing': [PASS, NO_VARIANTS],  # only in no-snap debug.
   'debug-stepin-call-function-stub': [PASS, NO_VARIANTS],  # only in no-snap debug.
-  'regress/regress-3717':[PASS, NO_VARIANTS],  # only in no-snap mode.
+  'regress/regress-3717': [PASS, NO_VARIANTS],  # only in no-snap mode.
+  'regress/regress-2451': [PASS, NO_VARIANTS],  # with custom snapshot and gc-stress.
+  'debug-multiple-breakpoints': [PASS, NO_VARIANTS],  # with custom snapshot and gc-stress.
 
   # TODO(mstarzinger): Optimizing top-level code flushed out some correctness
   # issues on ARM and ARM64.
   'es6/math-log2-log10': [PASS, NO_VARIANTS],  # on ARM and ARM64.
   'mirror-script': [PASS, NO_VARIANTS],  # on ARM64 only.
 
   # TODO(jarin/mstarzinger): Investigate debugger issues with TurboFan.
   'debug-evaluate-const': [PASS, NO_VARIANTS],
   'debug-evaluate-locals': [PASS, NO_VARIANTS],
   'debug-liveedit-check-stack': [PASS, NO_VARIANTS],  # only in no-snap mode.
@@ skipping 500 matching lines @@
   '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'
 ]