Re-land first pass BackgroundTracingManager.

content/browser/tracing/background_tracing_endpoint.cc

Index: content/browser/tracing/background_tracing_endpoint.cc
diff --git a/content/browser/tracing/background_tracing_endpoint.cc b/content/browser/tracing/background_tracing_endpoint.cc
new file mode 100644
index 0000000000000000000000000000000000000000..e4d275f57f5800e7a32d898d1cf7681d799325cf
--- /dev/null
+++ b/content/browser/tracing/background_tracing_endpoint.cc
@@ -0,0 +1,15 @@
+// Copyright 2015 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/browser/tracing/background_tracing_endpoint.h"
+
+BackgroundTracingEndpoint::BackgroundTracingEndpoint() {
+}
+
+BackgroundTracingEndpoint::~BackgroundTracingEndpoint() {
+}
+
+void BackgroundTracingEndpoint::SetDoneCallback(DoneCallback done_callback) {
+  done_callback_ = done_callback;
+}