Add tracing AutoOpenCloseEvent.

base/trace_event/vfc_persistent_async_event.cc

Index: base/trace_event/vfc_persistent_async_event.cc
diff --git a/base/trace_event/vfc_persistent_async_event.cc b/base/trace_event/vfc_persistent_async_event.cc
new file mode 100644
index 0000000000000000000000000000000000000000..b4d58be950708ff118a612d8f7ed00beefd24fc1
--- /dev/null
+++ b/base/trace_event/vfc_persistent_async_event.cc
@@ -0,0 +1,33 @@
+// Copyright 2016 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.
+
+#include "base/trace_event/vfc_persistent_async_event.h"
+
+#include "base/macros.h"
+#include "base/time/time.h"
+#include "base/trace_event/trace_event.h"
+
+namespace base {
+namespace trace_event {
+
+VFCPersistentAsyncEvent::VFCPersistentAsyncEvent(size_t id)
+  : PersistentAsyncEvent(id) {}
+
+VFCPersistentAsyncEvent::~VFCPersistentAsyncEvent() {}
+
+void VFCPersistentAsyncEvent::RecordStartEvent() {
+  TRACE_EVENT_ASYNC_BEGIN0("media,rail", "VideoPlayback", id_);
+}
+
+void VFCPersistentAsyncEvent::RecordStartEventWithTimestamp(int64_t timestamp) {
+  TRACE_EVENT_ASYNC_BEGIN_WITH_TIMESTAMP0(
+      "media,rail", "VideoPlayback", id_, timestamp);
+}
+
+void VFCPersistentAsyncEvent::RecordStopEvent() {
+  TRACE_EVENT_ASYNC_END0("media,rail", "VideoPlayback", id_);
+}
+
+}
+}