Implement frame attribution (FrameBlamer)

content/renderer/top_level_blame_context.cc

+// 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 "content/renderer/top_level_blame_context.h"
+
+#include "base/threading/platform_thread.h"
+#include "content/renderer/frame_blame_context.h"
+
+namespace content {
+
+const char kTopLevelBlameContextCategory[] = "blink";
+const char kTopLevelBlameContextName[] = "FrameBlameContext";
+const char kTopLevelBlameContextType[] = "TopLevel";
+const char kTopLevelBlameContextScope[] = "PlatformThread";
+
+TopLevelBlameContext::TopLevelBlameContext()
+    : base::trace_event::BlameContext(kTopLevelBlameContextCategory,
+                                      kTopLevelBlameContextName,
+                                      kTopLevelBlameContextType,
+                                      kTopLevelBlameContextScope,
+                                      base::PlatformThread::CurrentId(),
+                                      nullptr) {}
+
+}  // namespace content