Adding build-time option to enable the tracing of skia events in

skia/ext/skia_trace_shim.h

Index: skia/ext/skia_trace_shim.h
===================================================================
--- skia/ext/skia_trace_shim.h	(revision 0)
+++ skia/ext/skia_trace_shim.h	(revision 0)
@@ -0,0 +1,18 @@
+// 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.
+
+#ifndef SKIA_EXT_SKIA_TRACE_SHIM_H_
+#define SKIA_EXT_SKIA_TRACE_SHIM_H_
+#pragma once
+
+#include "base/debug/trace_event.h"
+
+#define SK_TRACE_EVENT0(name) \
+    TRACE_EVENT0("skia", name)
+#define SK_TRACE_EVENT1(name, arg1_name, arg1_val) \
+    TRACE_EVENT1("skia", name, arg1_name, arg1_val)
+#define SK_TRACE_EVENT2(name, arg1_name, arg1_val, arg2_name, arg2_val) \
+    TRACE_EVENT1("skia", name, arg1_name, arg1_val, arg2_name, arg2_val)
+
+#endif