Flush UKM metrics when backgrounded on Android and iOS.

chrome/browser/android/metrics/uma_session_stats.cc

 // Copyright 2015 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/android/metrics/uma_session_stats.h"
 
 #include "base/android/jni_array.h"
 #include "base/android/jni_string.h"
 #include "base/command_line.h"
 #include "base/metrics/histogram_macros.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/threading/sequenced_worker_pool.h"
 #include "base/time/time.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/metrics/chrome_metrics_service_accessor.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/pref_names.h"
 #include "chrome/installer/util/google_update_settings.h"
 #include "components/metrics/metrics_pref_names.h"
 #include "components/metrics/metrics_service.h"
 #include "components/metrics_services_manager/metrics_services_manager.h"
 #include "components/prefs/pref_service.h"
+#include "components/ukm/ukm_service.h"
 #include "components/variations/metrics_util.h"
 #include "components/variations/variations_associated_data.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/user_metrics.h"
 #include "jni/UmaSessionStats_jni.h"
 
 using base::android::ConvertJavaStringToUTF8;
 using base::android::JavaParamRef;
 using base::UserMetricsAction;
 
 namespace {
 UmaSessionStats* g_uma_session_stats = NULL;
 }  // namespace
 
 UmaSessionStats::UmaSessionStats()
     : active_session_count_(0) {
 }
 
 UmaSessionStats::~UmaSessionStats() {
 }
 
 void UmaSessionStats::UmaResumeSession(JNIEnv* env,
                                        const JavaParamRef<jobject>& obj) {
   DCHECK(g_browser_process);
 
   if (active_session_count_ == 0) {
     session_start_time_ = base::TimeTicks::Now();
 
-    // Tell the metrics service that the application resumes.
+    // Tell the metrics services that the application resumes.
     metrics::MetricsService* metrics = g_browser_process->metrics_service();
     if (metrics) {
       metrics->OnAppEnterForeground();
     }
+    ukm::UkmService* ukm_service = g_browser_process->ukm_service();
+    if (ukm_service) {

[Alexei Svitkine (slow), 2017/03/01 22:56:13]

Nit: No {}s

Remove them from metrics service case above and below as well.

[Bryan McQuade, 2017/03/01 23:06:50]

Done

+      ukm_service->OnAppEnterForeground();
+    }
   }
   ++active_session_count_;
 }
 
 void UmaSessionStats::UmaEndSession(JNIEnv* env,
                                     const JavaParamRef<jobject>& obj) {
   --active_session_count_;
   DCHECK_GE(active_session_count_, 0);
 
   if (active_session_count_ == 0) {
     base::TimeDelta duration = base::TimeTicks::Now() - session_start_time_;
 
     // Note: This metric is recorded separately on desktop in
     // DesktopSessionDurationTracker::EndSession.
     UMA_HISTOGRAM_LONG_TIMES("Session.TotalDuration", duration);
 
     DCHECK(g_browser_process);
-    // Tell the metrics service it was cleanly shutdown.
+    // Tell the metrics services they were cleanly shutdown.
     metrics::MetricsService* metrics = g_browser_process->metrics_service();
     if (metrics) {
       metrics->OnAppEnterBackground();
     }
+    ukm::UkmService* ukm_service = g_browser_process->ukm_service();
+    if (ukm_service) {
+      ukm_service->OnAppEnterBackground();
+    }
   }
 }
 
 // static
 void UmaSessionStats::RegisterSyntheticFieldTrial(
     const std::string& trial_name,
     const std::string& group_name) {
   ChromeMetricsServiceAccessor::RegisterSyntheticFieldTrial(trial_name,
                                                             group_name);
 }
@@ skipping 145 matching lines @@
   // We should have only one UmaSessionStats instance.
   DCHECK(!g_uma_session_stats);
   g_uma_session_stats = new UmaSessionStats();
   return reinterpret_cast<intptr_t>(g_uma_session_stats);
 }
 
 // Register native methods
 bool RegisterUmaSessionStats(JNIEnv* env) {
   return RegisterNativesImpl(env);
 }