Create a histogram serialization mechanism in components/metrics

base/metrics/linearhistogram_sample_chromeos.cc

Index: base/metrics/linearhistogram_sample_chromeos.cc
diff --git a/base/metrics/linearhistogram_sample_chromeos.cc b/base/metrics/linearhistogram_sample_chromeos.cc
new file mode 100644
index 0000000000000000000000000000000000000000..2f1b20ea435f121594c4120a51d31b3028812210
--- /dev/null
+++ b/base/metrics/linearhistogram_sample_chromeos.cc
@@ -0,0 +1,51 @@
+// 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/linearhistogram_sample_chromeos.h"
+
+#include <string>
+
+#include "base/metrics/metric_sample_chromeos.h"
+#include "base/strings/string_number_conversions.h"
+#include "base/strings/string_split.h"
+#include "base/strings/stringprintf.h"
+
+using std::string;
+using std::vector;
+
+namespace base {
+LinearHistogramSample::LinearHistogramSample(const std::string& histname,
+                                             int sample,
+                                             int max)
+    : MetricSample(MetricSample::LINEAR_HISTOGRAM, histname),
+      sample_(sample),
+      max_(max) {}
+
+LinearHistogramSample::~LinearHistogramSample() {}
+
+int LinearHistogramSample::sample() const { return sample_; }
+
+int LinearHistogramSample::max() const { return max_; }
+
+string LinearHistogramSample::ToString() const {
+  return StringPrintf(
+      "linearhistogram%c%s %d %d%c", '\0', name_.c_str(), sample_, max_, '\0');
+}
+
+LinearHistogramSample* LinearHistogramSample::ReadLinearHistogram(
+    const std::string& histogram_serialized) {
+  vector<string> parts;
+  int sample, max;
+  SplitString(histogram_serialized, ' ', &parts);
+  if (parts.size() != 3) {
+    return NULL;
+  }
+
+  if (!StringToInt(parts[1], &sample) || !StringToInt(parts[2], &max)) {
+    return NULL;
+  }
+
+  return new LinearHistogramSample(parts[0], sample, max);
+}
+}  // namespace base