Create a histogram serialization mechanism in components/metrics

base/metrics/metric_sample_chromeos.cc

Index: base/metrics/metric_sample_chromeos.cc
diff --git a/base/metrics/metric_sample_chromeos.cc b/base/metrics/metric_sample_chromeos.cc
new file mode 100644
index 0000000000000000000000000000000000000000..3bf71b4c714a2d4233b280cd625a049dfb25dac7
--- /dev/null
+++ b/base/metrics/metric_sample_chromeos.cc
@@ -0,0 +1,28 @@
+// 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 <string>
+
+#include "base/metrics/metric_sample_chromeos.h"
+
+using std::string;
+
+namespace base {
+MetricSample::MetricSample(MetricSample::SampleType sample_type,
+                           string metric_name)
+    : type_(sample_type), name_(metric_name) {}
+
+MetricSample::~MetricSample() {}
+
+bool MetricSample::IsValid() const {
+  return name_.find(' ') == string::npos && name_.find('\0') == string::npos;
+}
+
+MetricSample::SampleType MetricSample::type() const { return type_; }
+
+string MetricSample::name() const { return name_; }
+
+string MetricSample::ToString() const { return "not implemented"; }
+
+}  // namespace base