crostini: Engagement metrics

We track time with a GUI window in foreground and time with Crostini
running in the background. We do not yet track time with a terminal
browser window in foreground.
Note that the actual metric-emitting code is at
https://osscs.corp.google.com/chromium/chromium/src/+/master:components/guest_os/guest_os_engagement_metrics.cc;l=177;drc=4cc56e90bebaf1df23e738c19b88463cb4e2f366

Bug: chromium:1007139
Test: Deploy, use Crostini, check chrome://histograms
Change-Id: Ib7b0d6d88d7c0a4d94fcb3c399c41a243ccccbe1
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2586649
Commit-Queue: David Munro <davidmunro@google.com>
Reviewed-by: Nicholas Verne <nverne@chromium.org>
Reviewed-by: Alexander Alekseev <alemate@chromium.org>
Reviewed-by: Caitlin Fischer <caitlinfischer@google.com>
Reviewed-by: Timothy Loh <timloh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#838580}

chrome/browser/chromeos/BUILD.gn

@@ -1086,6 +1086,8 @@ source_set("chromeos") {
     "crostini/ansible/ansible_management_service_factory.h",
     "crostini/crostini_disk.cc",
     "crostini/crostini_disk.h",
+    "crostini/crostini_engagement_metrics_service.cc",
+    "crostini/crostini_engagement_metrics_service.h",
     "crostini/crostini_export_import.cc",
     "crostini/crostini_export_import.h",
     "crostini/crostini_export_import_notification_controller.cc",

chrome/browser/chromeos/browser_context_keyed_service_factories.cc

@@ -10,6 +10,7 @@
 #include "chrome/browser/chromeos/authpolicy/authpolicy_credentials_manager.h"
 #include "chrome/browser/chromeos/bluetooth/debug_logs_manager_factory.h"
 #include "chrome/browser/chromeos/cert_provisioning/cert_provisioning_scheduler_user_service.h"
+#include "chrome/browser/chromeos/crostini/crostini_engagement_metrics_service.h"
 #include "chrome/browser/chromeos/extensions/file_manager/event_router_factory.h"
 #include "chrome/browser/chromeos/extensions/input_method_api.h"
 #include "chrome/browser/chromeos/extensions/login_screen/login_state/session_state_changed_event_dispatcher.h"
@@ -61,6 +62,7 @@ void EnsureBrowserContextKeyedServiceFactoriesBuilt() {
   cert_provisioning::CertProvisioningSchedulerUserServiceFactory::GetInstance();
   chromeos::full_restore::FullRestoreServiceFactory::GetInstance();
   CroshLoaderFactory::GetInstance();
+  crostini::CrostiniEngagementMetricsService::Factory::GetInstance();
 #if defined(USE_CUPS)
   CupsProxyServiceManagerFactory::GetInstance();
 #endif

chrome/browser/chromeos/crostini/crostini_engagement_metrics_service.cc

+// Copyright 2020 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/chromeos/crostini/crostini_engagement_metrics_service.h"
+
+#include "chrome/browser/chromeos/crostini/crostini_features.h"
+#include "chrome/browser/chromeos/crostini/crostini_pref_names.h"
+#include "chrome/browser/chromeos/crostini/crostini_util.h"
+#include "chrome/browser/profiles/profile.h"
+#include "components/keyed_service/content/browser_context_dependency_manager.h"
+
+namespace crostini {
+
+constexpr char kUmaPrefix[] = "Crostini";
+
+CrostiniEngagementMetricsService*
+CrostiniEngagementMetricsService::Factory::GetForProfile(Profile* profile) {
+  return static_cast<CrostiniEngagementMetricsService*>(
+      GetInstance()->GetServiceForBrowserContext(profile, true));
+}
+
+CrostiniEngagementMetricsService::Factory*
+CrostiniEngagementMetricsService::Factory::GetInstance() {
+  static base::NoDestructor<CrostiniEngagementMetricsService::Factory> factory;
+  return factory.get();
+}
+
+CrostiniEngagementMetricsService::Factory::Factory()
+    : BrowserContextKeyedServiceFactory(
+          "CrostiniEngagementMetricsService",
+          BrowserContextDependencyManager::GetInstance()) {}
+
+CrostiniEngagementMetricsService::Factory::~Factory() = default;
+
+KeyedService*
+CrostiniEngagementMetricsService::Factory::BuildServiceInstanceFor(
+    content::BrowserContext* context) const {
+  Profile* profile = Profile::FromBrowserContext(context);
+  return new CrostiniEngagementMetricsService(profile);
+}
+
+bool CrostiniEngagementMetricsService::Factory::
+    ServiceIsCreatedWithBrowserContext() const {
+  return true;
+}
+
+bool CrostiniEngagementMetricsService::Factory::ServiceIsNULLWhileTesting()
+    const {
+  // Checking whether Crostini is allowed requires more setup than is present
+  // in most unit tests.
+  return true;
+}
+
+CrostiniEngagementMetricsService::CrostiniEngagementMetricsService(
+    Profile* profile) {
+  if (!CrostiniFeatures::Get()->IsEnabled(profile))
+    return;
+  guest_os_engagement_metrics_ =
+      std::make_unique<guest_os::GuestOsEngagementMetrics>(
+          profile->GetPrefs(), base::BindRepeating(IsCrostiniWindow),
+          prefs::kEngagementPrefsPrefix, kUmaPrefix);
+}
+
+CrostiniEngagementMetricsService::~CrostiniEngagementMetricsService() = default;
+
+void CrostiniEngagementMetricsService::SetBackgroundActive(
+    bool background_active) {
+  // If policy changes to enable Crostini, we won't have created the helper
+  // object. This should be relatively rare so for now we don't track this
+  // case.
+  if (!guest_os_engagement_metrics_)
+    return;
+  guest_os_engagement_metrics_->SetBackgroundActive(background_active);
+}
+
+}  // namespace crostini

chrome/browser/chromeos/crostini/crostini_engagement_metrics_service.h

+// Copyright 2020 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_CHROMEOS_CROSTINI_CROSTINI_ENGAGEMENT_METRICS_SERVICE_H_
+#define CHROME_BROWSER_CHROMEOS_CROSTINI_CROSTINI_ENGAGEMENT_METRICS_SERVICE_H_
+
+#include "base/macros.h"
+#include "base/no_destructor.h"
+#include "components/guest_os/guest_os_engagement_metrics.h"
+#include "components/keyed_service/content/browser_context_keyed_service_factory.h"
+#include "components/keyed_service/core/keyed_service.h"
+
+class Profile;
+
+namespace crostini {
+
+// A KeyedService for tracking engagement with Crostini, reporting values as
+// per GuestOsEngagementMetrics.
+class CrostiniEngagementMetricsService : public KeyedService {
+ public:
+  class Factory : public BrowserContextKeyedServiceFactory {
+   public:
+    static CrostiniEngagementMetricsService* GetForProfile(Profile* profile);
+    static Factory* GetInstance();
+
+   private:
+    friend class base::NoDestructor<Factory>;
+
+    Factory();
+    ~Factory() override;
+
+    // BrowserContextKeyedServiceFactory:
+    KeyedService* BuildServiceInstanceFor(
+        content::BrowserContext* context) const override;
+    bool ServiceIsCreatedWithBrowserContext() const override;
+    bool ServiceIsNULLWhileTesting() const override;
+  };
+
+  explicit CrostiniEngagementMetricsService(Profile* profile);
+  ~CrostiniEngagementMetricsService() override;
+
+  // This needs to be called when Crostini starts and stops being active so we
+  // can correctly track background active time.
+  void SetBackgroundActive(bool background_active);
+
+ private:
+  std::unique_ptr<guest_os::GuestOsEngagementMetrics>
+      guest_os_engagement_metrics_;
+
+  DISALLOW_COPY_AND_ASSIGN(CrostiniEngagementMetricsService);
+};
+
+}  // namespace crostini
+
+#endif  // CHROME_BROWSER_CHROMEOS_CROSTINI_CROSTINI_ENGAGEMENT_METRICS_SERVICE_H_

chrome/browser/chromeos/crostini/crostini_manager.cc

@@ -29,6 +29,7 @@
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/browser_process_platform_part.h"
 #include "chrome/browser/chromeos/crostini/ansible/ansible_management_service.h"
+#include "chrome/browser/chromeos/crostini/crostini_engagement_metrics_service.h"
 #include "chrome/browser/chromeos/crostini/crostini_features.h"
 #include "chrome/browser/chromeos/crostini/crostini_manager_factory.h"
 #include "chrome/browser/chromeos/crostini/crostini_port_forwarder.h"
@@ -2569,6 +2570,13 @@ void CrostiniManager::OnContainerStarted(
     return;
   ContainerId container_id(signal.vm_name(), signal.container_name());
 
+  auto* engagement_metrics_service =
+      CrostiniEngagementMetricsService::Factory::GetForProfile(profile_);
+  // This is null in unit tests.
+  if (engagement_metrics_service) {
+    engagement_metrics_service->SetBackgroundActive(true);
+  }
+
   running_containers_.emplace(
       signal.vm_name(),
       ContainerInfo(signal.container_name(), signal.container_username(),
@@ -2667,6 +2675,14 @@ void CrostiniManager::OnContainerShutdown(
       break;
     }
   }
+  if (running_containers_.empty()) {
+    auto* engagement_metrics_service =
+        CrostiniEngagementMetricsService::Factory::GetForProfile(profile_);
+    // This is null in unit tests.
+    if (engagement_metrics_service) {
+      engagement_metrics_service->SetBackgroundActive(false);
+    }
+  }
 }
 
 void CrostiniManager::OnInstallLinuxPackageProgress(

chrome/browser/chromeos/crostini/crostini_pref_names.cc

@@ -10,6 +10,7 @@
 #include "base/values.h"
 #include "chrome/browser/chromeos/crostini/crostini_simple_types.h"
 #include "chrome/browser/chromeos/crostini/crostini_util.h"
+#include "components/guest_os/guest_os_prefs.h"
 #include "components/pref_registry/pref_registry_syncable.h"
 #include "components/prefs/pref_registry_simple.h"
 
@@ -85,6 +86,9 @@ const char kCrostiniPortForwarding[] = "crostini.port_forwarding.ports";
 const char kCrostiniArcAdbSideloadingUserPref[] =
     "crostini.arc_adb_sideloading.user_pref";
 
+// Prefix for storing engagement time data, per GuestOSEngagementMetrics.
+const char kEngagementPrefsPrefix[] = "crostini.metrics";
+
 void RegisterProfilePrefs(PrefRegistrySimple* registry) {
   registry->RegisterBooleanPref(kCrostiniEnabled, false);
   registry->RegisterDictionaryPref(kCrostiniMimeTypes);
@@ -129,6 +133,9 @@ void RegisterProfilePrefs(PrefRegistrySimple* registry) {
   registry->RegisterIntegerPref(
       kCrostiniArcAdbSideloadingUserPref,
       static_cast<int>(CrostiniArcAdbSideloadingUserAllowanceMode::kDisallow));
+
+  guest_os::prefs::RegisterEngagementProfilePrefs(registry,
+                                                  kEngagementPrefsPrefix);
 }
 
 }  // namespace prefs

chrome/browser/chromeos/crostini/crostini_pref_names.h

@@ -42,6 +42,8 @@ extern const char kCrostiniLastLaunchTimeWindowStart[];
 extern const char kCrostiniLastDiskSize[];
 extern const char kCrostiniPortForwarding[];
 
+extern const char kEngagementPrefsPrefix[];
+
 void RegisterProfilePrefs(PrefRegistrySimple* registry);
 
 }  // namespace prefs

chrome/browser/chromeos/crostini/crostini_util.cc

@@ -572,7 +572,12 @@ const ContainerId& DefaultContainerId() {
   return *container_id;
 }
 
-bool IsCrostiniWindow(aura::Window* window) {
+bool IsCrostiniWindow(const aura::Window* window) {
+  // TODO(crbug/1158644): Non-Crostini apps (borealis, ...) have also been
+  // identifying as Crostini. For now they're less common, and as they become
+  // more productionised they get their own app type (e.g. lacros), but at some
+  // point we'll want to untangle these different types to e.g. avoid double
+  // counting in usage metrics.
   return window->GetProperty(aura::client::kAppType) ==
          static_cast<int>(ash::AppType::CROSTINI_APP);
 }

chrome/browser/chromeos/crostini/crostini_util.h

@@ -209,7 +209,7 @@ void UpdateContainerPref(Profile* profile,
 
 const ContainerId& DefaultContainerId();
 
-bool IsCrostiniWindow(aura::Window* window);
+bool IsCrostiniWindow(const aura::Window* window);
 
 }  // namespace crostini
 

tools/metrics/histograms/histograms_xml/crostini/histograms.xml

@@ -241,6 +241,38 @@ reviews. Googlers can read more about this at go/gwsq-gerrit.
   </summary>
 </histogram>
 
+<histogram name="Crostini.EngagementTime.{Variant}" units="ms"
+    expires_after="2021-04-18">
+  <owner>davidmunro@google.com</owner>
+  <owner>clumptini@google.com</owner>
+  <summary>
+    {Variant} Engagement time metrics, along with foreground and background
+    time, are only collected on users with Crostini enabled. All four metrics
+    are accumulated and recorded to UMA once a day.
+  </summary>
+  <token key="Variant">
+    <variant name="Background"
+        summary="Times when a user is engaged and Crostini apps are running
+                 in the background, but the user isn't focusing on an
+                 Crostini app window."/>
+    <variant name="CrostiniTotal"
+        summary="Total of Crostini.EngagementTime.Background and .Foreground,
+                 which is the time the user is engaged and Crostini is
+                 running either in the foreground or background."/>
+    <variant name="Foreground"
+        summary="Times when a user is engaged and focuses on a Crostini GUI
+                 window. As of 2020-12-15 this may count some
+                 similar-but-not-quite-Crostini windows e.g. Bruschetta, see
+                 crbug/1158644 for more details."/>
+    <variant name="Total"
+        summary="Total CrOS user session time (from login to logout)
+                 excluding times when a user &quot;disengages&quot;. A user
+                 is disengaged when the screen is locked or dimmed due to
+                 user inactivity. For Total Crostini engagement time, see
+                 Crostini.EngagementTime.CrostiniTotal."/>
+  </token>
+</histogram>
+
 <histogram name="Crostini.FilesystemCorruption" enum="CorruptionStates"
     expires_after="2021-06-13">
   <owner>clumptini@google.com</owner>