Factor Google Now welcome notifications out of DesktopNotificationService.

chrome/browser/notifications/google_now_notification_stats_collector.cc

-// Copyright 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 "chrome/browser/notifications/google_now_notification_stats_collector.h"
-
-#include <string>
-
-#include "base/metrics/sparse_histogram.h"
-#include "chrome/browser/browser_process.h"
-#include "chrome/browser/notifications/notification.h"
-#include "chrome/browser/notifications/notification_ui_manager.h"
-#include "content/public/browser/user_metrics.h"
-#include "ui/message_center/notification.h"
-
-namespace {
-const char kChromeNowExtensionID[] = "pafkbggdmjlpgkdkcbjmhmfcdpncadgh";
-const int kNotificationsMaxCount = 20;
-}
-
-GoogleNowNotificationStatsCollector::GoogleNowNotificationStatsCollector(
-    message_center::MessageCenter* message_center)
-    : message_center_(message_center) {
-  message_center_->AddObserver(this);
-}
-
-GoogleNowNotificationStatsCollector::~GoogleNowNotificationStatsCollector() {
-  message_center_->RemoveObserver(this);
-}
-
-void GoogleNowNotificationStatsCollector::OnNotificationDisplayed(
-    const std::string& notification_id,
-    const message_center::DisplaySource source) {
-  if ((source == message_center::DISPLAY_SOURCE_POPUP) &&
-      IsNotificationIdForGoogleNow(notification_id)) {
-    content::RecordAction(
-        base::UserMetricsAction(
-            "GoogleNow.MessageCenter.NotificationPoppedUp"));
-  }
-}
-
-void GoogleNowNotificationStatsCollector::OnCenterVisibilityChanged(
-    message_center::Visibility visibility) {
-  if (visibility == message_center::VISIBILITY_MESSAGE_CENTER) {
-    UMA_HISTOGRAM_SPARSE_SLOWLY(
-        "GoogleNow.MessageCenter.Displayed.NotificationsVisible",
-        std::min(CountVisibleGoogleNowNotifications(), kNotificationsMaxCount));
-  }
-}
-
-bool GoogleNowNotificationStatsCollector::IsNotificationIdForGoogleNow(
-  const std::string& notification_id) {
-  bool isGoogleNowNotification = false;
-  const Notification* const notification =
-      g_browser_process->notification_ui_manager()->FindById(notification_id);
-  if (notification) {
-    isGoogleNowNotification =
-        ((notification->notifier_id().type ==
-              message_center::NotifierId::APPLICATION) &&
-        (notification->notifier_id().id == kChromeNowExtensionID));
-  }
-  return isGoogleNowNotification;
-}
-
-int GoogleNowNotificationStatsCollector::CountVisibleGoogleNowNotifications() {
-  typedef message_center::NotificationList::Notifications Notifications;
-  const Notifications visible_notifications =
-      message_center_->GetVisibleNotifications();
-  int google_now_notification_count = 0;
-  for (Notifications::iterator iter = visible_notifications.begin();
-      iter != visible_notifications.end();
-      ++iter) {
-    if ((*iter)->notifier_id().id == kChromeNowExtensionID)
-      google_now_notification_count++;
-  }
-  return google_now_notification_count;
-}