Tracing V2 prototype [NOT FOR REVIEW]

base/trace_event/trace_log.h

Index: base/trace_event/trace_log.h
diff --git a/base/trace_event/trace_log.h b/base/trace_event/trace_log.h
index 3f09674829381f30825e9ceea2734b0cf7111fc9..f883d519c8b4f98169326113f07e733ff336994f 100644
--- a/base/trace_event/trace_log.h
+++ b/base/trace_event/trace_log.h
@@ -21,6 +21,7 @@
 #include "base/trace_event/trace_config.h"
 #include "base/trace_event/trace_event_impl.h"
 #include "build/build_config.h"
+#include "base/trace_event/v2/ring_buffer.h"
 
 namespace base {
 
@@ -498,6 +499,11 @@ class BASE_EXPORT TraceLog : public MemoryDumpProvider {
   bool use_worker_thread_;
 
   DISALLOW_COPY_AND_ASSIGN(TraceLog);
+
+public:
+  static bool use_v2;
+  uint8_t v2_buf[1024 * 1024];
+  v2::RingBuffer v2_rb;
 };
 
 }  // namespace trace_event