Make TracedValue lower overhead.

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 599 matching lines @@
         'threading/thread_unittest.cc',
         'threading/watchdog_unittest.cc',
         'threading/worker_pool_posix_unittest.cc',
         'threading/worker_pool_unittest.cc',
         'time/pr_time_unittest.cc',
         'time/time_unittest.cc',
         'time/time_win_unittest.cc',
         'timer/hi_res_timer_manager_unittest.cc',
         'timer/timer_unittest.cc',
         'tools_sanity_unittest.cc',
+        'trace_event_value_unittest.cc',
         'tracked_objects_unittest.cc',
         'tuple_unittest.cc',
         'values_unittest.cc',
         'version_unittest.cc',
         'vlog_unittest.cc',
         'win/dllmain.cc',
         'win/enum_variant_unittest.cc',
         'win/event_trace_consumer_unittest.cc',
         'win/event_trace_controller_unittest.cc',
         'win/event_trace_provider_unittest.cc',
@@ skipping 673 matching lines @@
             'base_unittests.isolate',
           ],
           'sources': [
             'base_unittests.isolate',
           ],
         },
       ],
     }],
   ],
 }