Create a histogram serialization mechanism in components/metrics

base/metrics/metric_sample.cc

+// Copyright (c) 2014 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/metrics/metric_sample.h"
+
+#include "base/logging.h"
+
+namespace base {
+MetricSample::MetricSample(MetricSample::SampleType sample_type) {
+  type = sample_type;
+}
+
+MetricSample::SampleType MetricSample::getType() {
+  return type;
+}
+
+MetricSample::~MetricSample() {}
+
+int MetricSample::Write(int buffer_size, char* buffer) {
+  DLOG(ERROR) << "not implemented";
+  return -1;
+}
+}  // namespace base