Let MetricsService know about some Android Activities

chrome/browser/metrics/metrics_service_android.cc

Index: chrome/browser/metrics/metrics_service_android.cc
diff --git a/chrome/browser/metrics/metrics_service_android.cc b/chrome/browser/metrics/metrics_service_android.cc
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+++ b/chrome/browser/metrics/metrics_service_android.cc
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+// 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.
+
+#include "chrome/browser/metrics/metrics_service.h"
+
+#include "base/metrics/histogram.h"
+#include "base/prefs/pref_registry_simple.h"
+#include "base/prefs/pref_service.h"
+#include "base/prefs/scoped_user_pref_update.h"
+#include "base/values.h"
+#include "chrome/browser/android/activity_type_ids.h"
+#include "chrome/browser/browser_process.h"
+#include "chrome/common/pref_names.h"
+
+namespace {
+
+// Increments a particular entry in the ListValue.
+void IncrementListValue(base::ListValue* counts, int index) {
+  int current_count = 0;
+  counts->GetInteger(index, &current_count);
+  counts->Set(index, new base::FundamentalValue(current_count + 1));
+}
+
+// Takes an int corresponding to a Type and returns the corresponding flag.
+int GetActivityFlag(int type_id) {
+  ActivityTypeIds::Type type = ActivityTypeIds::GetActivityType(type_id);
+  CHECK(type < ActivityTypeIds::ACTIVITY_MAX_VALUE);
+  return (1 << type);
+}
+
+}  // namespace
+
+// static
+void MetricsService::RegisterPrefsAndroid(PrefRegistrySimple* registry) {
+  registry->RegisterIntegerPref(prefs::kStabilityForegroundActivityType,
+                                ActivityTypeIds::ACTIVITY_NONE);
+  registry->RegisterIntegerPref(prefs::kStabilityLaunchedActivityFlags, 0);
+  registry->RegisterListPref(prefs::kStabilityLaunchedActivityCounts);
+  registry->RegisterListPref(prefs::kStabilityCrashedActivityCounts);
+}
+
+void MetricsService::RecordAndroidStabilityPrefs(PrefService* pref) {
+  // Track which Activities were launched by the user.
+  // A 'launch' is defined as starting the Activity at least once during a
+  // UMA session.  Multiple launches are counted only once since it is possible
+  // for users to hop between Activities (e.g. entering and leaving Settings).
+  int launched = pref->GetInteger(prefs::kStabilityLaunchedActivityFlags);
+  ListPrefUpdate update_launches(pref, prefs::kStabilityLaunchedActivityCounts);
+  base::ListValue* launch_counts = update_launches.Get();
+  for (int activity_type = ActivityTypeIds::ACTIVITY_NONE;
+       activity_type < ActivityTypeIds::ACTIVITY_MAX_VALUE;
+       ++activity_type) {
+    if (launched & GetActivityFlag(activity_type))
+      IncrementListValue(launch_counts, activity_type);
+  }
+  pref->SetInteger(prefs::kStabilityLaunchedActivityFlags, 0);
+
+  // Track any Activities that were in the foreground when Chrome died.
+  // These Activities failed to be recorded as leaving the foreground, so Chrome
+  // couldn't have ended the UMA session cleanly.  Record them as crashing.
+  int foreground = pref->GetInteger(prefs::kStabilityForegroundActivityType);
+  if (foreground != ActivityTypeIds::ACTIVITY_NONE) {
+    ListPrefUpdate update_crashes(pref, prefs::kStabilityCrashedActivityCounts);
+    base::ListValue* crash_counts = update_crashes.Get();
+    IncrementListValue(crash_counts, foreground);
+    pref->SetInteger(prefs::kStabilityForegroundActivityType,
+                     ActivityTypeIds::ACTIVITY_NONE);
+  }
+
+  pref->CommitPendingWrite();
+}
+
+void MetricsService::RecordAndroidStabilityHistograms(PrefService* pref) {
+  ListPrefUpdate launch_updater(pref, prefs::kStabilityLaunchedActivityCounts);
+  ListPrefUpdate crash_updater(pref, prefs::kStabilityCrashedActivityCounts);
+
+  base::ListValue* launch_counts = launch_updater.Get();
+  base::ListValue* crash_counts = crash_updater.Get();
+
+  for (int activity_type = ActivityTypeIds::ACTIVITY_NONE;
+       activity_type < ActivityTypeIds::ACTIVITY_MAX_VALUE;
+       ++activity_type) {
+    int launch_count = 0;
+    int crash_count = 0;
+
+    launch_counts->GetInteger(activity_type, &launch_count);
+    crash_counts->GetInteger(activity_type, &crash_count);
+
+    for (int count = 0; count < launch_count; ++count) {
+      UMA_STABILITY_HISTOGRAM_ENUMERATION(
+          "Chrome.Android.Activity.LaunchCounts",
+          activity_type,
+          ActivityTypeIds::ACTIVITY_MAX_VALUE);
+    }
+
+    for (int count = 0; count < crash_count; ++count) {
+      UMA_STABILITY_HISTOGRAM_ENUMERATION("Chrome.Android.Activity.CrashCounts",
+                                          activity_type,
+                                          ActivityTypeIds::ACTIVITY_MAX_VALUE);
+    }
+  }
+
+  launch_counts->Clear();
+  crash_counts->Clear();
+}
+
+void MetricsService::OnForegroundActivityChanged(PrefService* pref,
+                                                 ActivityTypeIds::Type type) {
+  DCHECK(type < ActivityTypeIds::ACTIVITY_MAX_VALUE);
+
+  int activity_type = pref->GetInteger(prefs::kStabilityForegroundActivityType);
+  if (activity_type == type)
+    return;
+
+  // Record that the Activity is now in the foreground.
+  pref->SetInteger(prefs::kStabilityForegroundActivityType, type);
+
+  // Record that the Activity was launched this sesaion.
+  // The pref stores a set of flags ORed together, where each set flag
+  // corresponds to a launched Activity type.
+  int launched = pref->GetInteger(prefs::kStabilityLaunchedActivityFlags);
+  if (type != ActivityTypeIds::ACTIVITY_NONE) {
+    launched |= GetActivityFlag(type);
+    pref->SetInteger(prefs::kStabilityLaunchedActivityFlags, launched);
+  }
+
+  pref->CommitPendingWrite();
+}
+
+// static
+void MetricsService::DiscardOldStabilityStatsAndroid(PrefService* local_state) {
+  local_state->SetInteger(prefs::kStabilityForegroundActivityType,
+                          ActivityTypeIds::ACTIVITY_NONE);
+  local_state->SetInteger(prefs::kStabilityLaunchedActivityFlags, 0);
+
+  ListPrefUpdate launches(local_state, prefs::kStabilityLaunchedActivityCounts);
+  launches.Get()->Clear();
+
+  ListPrefUpdate crashes(local_state, prefs::kStabilityCrashedActivityCounts);
+  crashes.Get()->Clear();
+}