Add UMA histogram data representing the Synced Notifications feature.

chrome/browser/notifications/sync_notifier/synced_notification_stats.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_NOTIFICATIONS_SYNC_NOTIFIER_SYNCED_NOTIFICATION_STATS_H_
+#define CHROME_BROWSER_NOTIFICATIONS_SYNC_NOTIFIER_SYNCED_NOTIFICATION_STATS_H_
+
+#include <string>
+
+#include "base/basictypes.h"
+
+namespace notifier {
+
+enum SyncedNotificationActionType {
+  SYNCED_NOTIFICATION_ACTION_UNKNOWN,
+  SYNCED_NOTIFICATION_ACTION_CLICK,
+  SYNCED_NOTIFICATION_ACTION_BUTTON_CLICK,
+  SYNCED_NOTIFICATION_ACTION_CLOSE_BY_USER,
+  SYNCED_NOTIFICATION_ACTION_CLOSE_BY_SYSTEM,
+  SYNCED_NOTIFICATION_ACTION_TOAST_TIMEOUT,
+  // NOTE: Add new action types only immediately above this line. Also,
+  // make sure the enum list in tools/histogram/histograms.xml is
+  // updated with any change in here.
+  SYNCED_NOTIFICATION_ACTION_COUNT
+};
+
+// Represents the aggregate stats for each notification.
+class SyncedNotificationStats {
+ public:
+  // Default constructor for map.
+  SyncedNotificationStats();
+
+  explicit SyncedNotificationStats(const std::string& id);
+  virtual ~SyncedNotificationStats();
+
+  // Called when we get an action from the message center.
+  void CollectAction(SyncedNotificationActionType type);
+
+ private:
+  std::string id_;
+};
+
+}  // namespace notifier
+
+#endif  // CHROME_BROWSER_NOTIFICATIONS_SYNC_NOTIFIER_SYNCED_NOTIFICATION_STATS_H_