Don't call exit() after __debugbreak() on release builds.

base/base.gyp

 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 {
   'variables': {
     'chromium_code': 1,
   },
   'includes': [
     '../build/win_precompile.gypi',
@@ skipping 461 matching lines @@
         'cancelable_callback_unittest.cc',
         'command_line_unittest.cc',
         'containers/adapters_unittest.cc',
         'containers/hash_tables_unittest.cc',
         'containers/linked_list_unittest.cc',
         'containers/mru_cache_unittest.cc',
         'containers/small_map_unittest.cc',
         'containers/stack_container_unittest.cc',
         'cpu_unittest.cc',
         'debug/crash_logging_unittest.cc',
+        'debug/debugger_unittest.cc',
         'debug/leak_tracker_unittest.cc',
         'debug/proc_maps_linux_unittest.cc',
         'debug/stack_trace_unittest.cc',
         'debug/task_annotator_unittest.cc',
         'debug/trace_event_argument_unittest.cc',
         'debug/trace_event_memory_unittest.cc',
         'debug/trace_event_synthetic_delay_unittest.cc',
         'debug/trace_event_system_stats_monitor_unittest.cc',
         'debug/trace_event_unittest.cc',
         'debug/trace_event_unittest.h',
@@ skipping 1061 matching lines @@
               'dependencies': [
                 '../tools/xdisplaycheck/xdisplaycheck.gyp:xdisplaycheck',
               ],
             }],
           ],
         },
       ],
     }],
   ],
 }