Implement tracing interface for v8

tools/gyp/v8.gyp

 # 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
 #       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 842 matching lines @@
         '../../src/string-stream.cc',
         '../../src/string-stream.h',
         '../../src/strings-storage.cc',
         '../../src/strings-storage.h',
         '../../src/strtod.cc',
         '../../src/strtod.h',
         '../../src/ic/stub-cache.cc',
         '../../src/ic/stub-cache.h',
         '../../src/token.cc',
         '../../src/token.h',
+        '../../src/tracing/event-tracer.cc',
+        '../../src/tracing/trace-event.h',
         '../../src/transitions-inl.h',
         '../../src/transitions.cc',
         '../../src/transitions.h',
         '../../src/type-feedback-vector-inl.h',
         '../../src/type-feedback-vector.cc',
         '../../src/type-feedback-vector.h',
         '../../src/type-info.cc',
         '../../src/type-info.h',
         '../../src/types-inl.h',
         '../../src/types.cc',
@@ skipping 943 matching lines @@
         }],
         ['want_separate_host_toolset==1', {
           'toolsets': ['host'],
         }, {
           'toolsets': ['target'],
         }],
       ],
     },
   ],
 }