Factor ChromeOS specific code out of MetricsLog.

chrome/browser/metrics/metrics_log_chromeos.h

+// Copyright 2013 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.
+
+#ifndef CHROME_BROWSER_METRICS_METRICS_LOG_CHROMEOS_H_
+#define CHROME_BROWSER_METRICS_METRICS_LOG_CHROMEOS_H_
+
+#include "chrome/browser/metrics/perf_provider_chromeos.h"
+
+namespace device {
+class BluetoothAdapter;
+}
+
+namespace metrics {
+class ChromeUserMetricsExtension;
+}
+
+class PrefService;
+
+// Performs ChromeOS specific metrics logging.
+class MetricsLogChromeOS {
+ public:
+  explicit MetricsLogChromeOS(metrics::ChromeUserMetricsExtension* uma_proto);
+  virtual ~MetricsLogChromeOS();
+
+  // Logs ChromeOS specific metrics which don't need to be updated immediately.
+  void LogChromeOSMetrics();
+
+  // Within the stability group, write ChromeOS specific attributes that need to
+  // be updated asap and can't be delayed until the user decides to restart
+  // chromium.  Delaying these stats would bias metrics away from happy long
+  // lived chromium processes (ones that don't crash, and keep on running).
+  void WriteRealtimeStabilityAttributes(

[ramant (doing other things), 2014/02/03 17:45:27]

nit: line#33 and 34 could be combined into one line.

[tdresser, 2014/02/03 17:55:34]

Done.

+      PrefService* pref);
+
+ private:
+  // Update the number of users logged into a multi-profile session.
+  // If the number of users change while the log is open, the call invalidates
+  // the user count value.
+  void UpdateMultiProfileUserCount();
+
+  // Sets the Bluetooth Adapter instance used for the WriteBluetoothProto()
+  // call.
+  void SetBluetoothAdapter(scoped_refptr<device::BluetoothAdapter> adapter);
+
+  // Writes info about paired Bluetooth devices on this system.
+  virtual void WriteBluetoothProto();
+
+  metrics::PerfProvider perf_provider_;
+
+  // Bluetooth Adapter instance for collecting information about paired devices.
+  scoped_refptr<device::BluetoothAdapter> adapter_;
+  metrics::ChromeUserMetricsExtension* uma_proto_;
+
+  DISALLOW_COPY_AND_ASSIGN(MetricsLogChromeOS);
+};
+
+#endif  // CHROME_BROWSER_METRICS_METRICS_LOG_CHROMEOS_H_