[Sheriff] Mark test-debug/* as flaky on Mac.

test/cctest/cctest.status

 # Copyright 2011 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 66 matching lines @@
   'test-cpu-profiler/JsNativeJsSample': [PASS, FLAKY],
 
   # BUG(3055).
   'test-cpu-profiler/JsNative1JsNative2JsSample': [PASS, ['mode == release', FAIL], ['mode == debug', FLAKY]],
 
   # BUG(3005).
   'test-alloc/CodeRange': [PASS, FAIL],
 }],  # 'system == windows'
 
 ##############################################################################
+['system == macos', {
+
+  # BUG(3125).
+  'test-debug/*': [PASS, ['mode == debug', FLAKY]],
+}],  # 'system == macos'
+
+##############################################################################
 ['arch == arm', {
 
   # We cannot assume that we can throw OutOfMemory exceptions in all situations.
   # Apparently our ARM box is in such a state. Skip the test as it also runs for
   # a long time.
   'test-api/OutOfMemory': [SKIP],
   'test-api/OutOfMemoryNested': [SKIP],
 
   # BUG(355): Test crashes on ARM.
   'test-log/ProfLazyMode': [SKIP],
@@ skipping 65 matching lines @@
   # Profiling doesn't work on Native Client.
   'test-cpu-profiler/*': [SKIP],
 
   # Fails since 16322 (new test).
   'test-code-stubs-arm/ConvertDToI': [SKIP],
 
   # BUG(2998).
   'test-macro-assembler-arm/LoadAndStoreWithRepresentation': [SKIP],
 }],  # 'arch == nacl_ia32 or arch == nacl_x64'
 ]