Factor ChromeOS specific code out of MetricsLog.

chrome/browser/metrics/metrics_log_chromeos.h

+// Copyright (c) 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/chromeos/login/user_manager.h"
+#include "chrome/browser/metrics/perf_provider_chromeos.h"
+#include "chrome/common/metrics/proto/chrome_user_metrics_extension.pb.h"
+#include "chrome/common/metrics/proto/system_profile.pb.h"
+#include "ui/events/event_utils.h"
+#include "ui/events/x/touch_factory_x11.h"

[Alexei Svitkine (slow), 2014/01/30 18:17:54]

Do you need all these includes in the header? For that that aren't needed by the
header, move them to the .cc file.

[tdresser, 2014/01/30 19:32:30]

Done.

+
+namespace device {
+class BluetoothAdapter;
+}
+
+// Performs ChromeOS specific metrics logging.
+class MetricsLogChromeOS {
+ public:
+  explicit MetricsLogChromeOS(metrics::SystemProfileProto* system_profile);
+  virtual ~MetricsLogChromeOS();
+
+  void LogChromeOSMetrics(

[Alexei Svitkine (slow), 2014/01/30 18:17:54]

Add a short comment about each of these methods.

[tdresser, 2014/01/30 19:32:30]

Done.

+      metrics::SystemProfileProto* system_profile,
+      metrics::ChromeUserMetricsExtension* uma_proto);
+  void WriteRealtimeStabilityAttributes(
+      PrefService* pref,
+      metrics::SystemProfileProto::Stability* stability);
+
+ 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(
+      metrics::SystemProfileProto* system_profile);
+
+  void WriteExternalTouchscreensProto(
+      metrics::SystemProfileProto::Hardware* hardware);
+
+  // 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::SystemProfileProto::Hardware* hardware);
+
+  metrics::PerfProvider perf_provider_;
+  // Bluetooth Adapter instance for collecting information about paired devices.

[Alexei Svitkine (slow), 2014/01/30 18:17:54]

Nit: Add an empty line before this comment.

[tdresser, 2014/01/30 19:32:30]

Done.

+  scoped_refptr<device::BluetoothAdapter> adapter_;
+
+  DISALLOW_COPY_AND_ASSIGN(MetricsLogChromeOS);
+};
+
+#endif  // CHROME_BROWSER_METRICS_METRICS_LOG_CHROMEOS_H_