Use CONTINUE_ON_SHUTDOWN for IncidentReportingService tasks.

chrome/browser/safe_browsing/incident_reporting/incident_reporting_service.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/safe_browsing/incident_reporting/incident_reporting_service.h"
 
 #include <math.h>
 #include <stddef.h>
 
 #include <algorithm>
 #include <utility>
 #include <vector>
 
 #include "base/macros.h"
 #include "base/memory/ptr_util.h"
 #include "base/metrics/field_trial.h"
 #include "base/metrics/histogram.h"
 #include "base/process/process_info.h"
 #include "base/single_thread_task_runner.h"
 #include "base/stl_util.h"
 #include "base/strings/string_util.h"
 #include "base/thread_task_runner_handle.h"
 #include "base/threading/sequenced_worker_pool.h"
 #include "build/build_config.h"
+#include "chrome/browser/browser_hangs_experiment.h"
 #include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/metrics/chrome_metrics_service_accessor.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/safe_browsing/incident_reporting/environment_data_collection.h"
 #include "chrome/browser/safe_browsing/incident_reporting/extension_data_collection.h"
 #include "chrome/browser/safe_browsing/incident_reporting/incident.h"
 #include "chrome/browser/safe_browsing/incident_reporting/incident_receiver.h"
 #include "chrome/browser/safe_browsing/incident_reporting/incident_report_uploader_impl.h"
 #include "chrome/browser/safe_browsing/incident_reporting/preference_validation_delegate.h"
 #include "chrome/browser/safe_browsing/incident_reporting/state_store.h"
@@ skipping 104 matching lines @@
     case MinimumProfileConsent::SAFE_BROWSING_ENABLED:
       return true;
     case MinimumProfileConsent::SAFE_BROWSING_EXTENDED_REPORTING_ENABLED:
       return profile->GetPrefs()->GetBoolean(
           prefs::kSafeBrowsingExtendedReportingEnabled);
   }
   NOTREACHED();
   return false;
 }
 
+// Returns the shutdown behavior for the task runners of the incident reporting
+// service. Current metrics suggest that CONTINUE_ON_SHUTDOWN will reduce the
+// number of browser hangs on shutdown.
+base::SequencedWorkerPool::WorkerShutdown GetShutdownBehavior() {
+  return IsBrowserHangsExperimentEnabled()
+             ? base::SequencedWorkerPool::CONTINUE_ON_SHUTDOWN
+             : base::SequencedWorkerPool::SKIP_ON_SHUTDOWN;
+}
+
 }  // namespace
 
 struct IncidentReportingService::ProfileContext {
   ProfileContext();
   ~ProfileContext();
 
   // Returns true if the profile has incidents to be uploaded or cleared.
   bool HasIncidents() const;
 
   // The incidents collected for this profile pending creation and/or upload.
@@ skipping 172 matching lines @@
     SafeBrowsingService* safe_browsing_service)
     : database_manager_(safe_browsing_service
                             ? safe_browsing_service->database_manager()
                             : nullptr),
       url_request_context_getter_(
           safe_browsing_service ? safe_browsing_service->url_request_context()
                                 : nullptr),
       collect_environment_data_fn_(&CollectEnvironmentData),
       environment_collection_task_runner_(
           content::BrowserThread::GetBlockingPool()
-              ->GetTaskRunnerWithShutdownBehavior(
-                  base::SequencedWorkerPool::SKIP_ON_SHUTDOWN)),
+              ->GetTaskRunnerWithShutdownBehavior(GetShutdownBehavior())),
       environment_collection_pending_(),
       collation_timeout_pending_(),
       collation_timer_(FROM_HERE,
                        base::TimeDelta::FromMilliseconds(kDefaultUploadDelayMs),
                        this,
                        &IncidentReportingService::OnCollationTimeout),
       delayed_analysis_callbacks_(
           base::TimeDelta::FromMilliseconds(kDefaultCallbackIntervalMs),
           content::BrowserThread::GetBlockingPool()
-              ->GetTaskRunnerWithShutdownBehavior(
-                  base::SequencedWorkerPool::SKIP_ON_SHUTDOWN)),
+              ->GetTaskRunnerWithShutdownBehavior(GetShutdownBehavior())),
       extended_reporting_only_delayed_analysis_callbacks_(
           base::TimeDelta::FromMilliseconds(kDefaultCallbackIntervalMs),
           content::BrowserThread::GetBlockingPool()
-              ->GetTaskRunnerWithShutdownBehavior(
-                  base::SequencedWorkerPool::SKIP_ON_SHUTDOWN)),
+              ->GetTaskRunnerWithShutdownBehavior(GetShutdownBehavior())),
       download_metadata_manager_(content::BrowserThread::GetBlockingPool()),
       receiver_weak_ptr_factory_(this),
       weak_ptr_factory_(this) {
   notification_registrar_.Add(this,
                               chrome::NOTIFICATION_PROFILE_ADDED,
                               content::NotificationService::AllSources());
   notification_registrar_.Add(this,
                               chrome::NOTIFICATION_PROFILE_DESTROYED,
                               content::NotificationService::AllSources());
   DownloadProtectionService* download_protection_service =
@@ skipping 87 matching lines @@
     const scoped_refptr<net::URLRequestContextGetter>& request_context_getter,
     base::TimeDelta delayed_task_interval,
     const scoped_refptr<base::TaskRunner>& delayed_task_runner)
     : database_manager_(safe_browsing_service
                             ? safe_browsing_service->database_manager()
                             : NULL),
       url_request_context_getter_(request_context_getter),
       collect_environment_data_fn_(&CollectEnvironmentData),
       environment_collection_task_runner_(
           content::BrowserThread::GetBlockingPool()
-              ->GetTaskRunnerWithShutdownBehavior(
-                  base::SequencedWorkerPool::SKIP_ON_SHUTDOWN)),
+              ->GetTaskRunnerWithShutdownBehavior(GetShutdownBehavior())),
       environment_collection_pending_(),
       collation_timeout_pending_(),
       collation_timer_(FROM_HERE,
                        base::TimeDelta::FromMilliseconds(kDefaultUploadDelayMs),
                        this,
                        &IncidentReportingService::OnCollationTimeout),
       delayed_analysis_callbacks_(delayed_task_interval, delayed_task_runner),
       extended_reporting_only_delayed_analysis_callbacks_(delayed_task_interval,
                                                           delayed_task_runner),
       download_metadata_manager_(content::BrowserThread::GetBlockingPool()),
@@ skipping 12 matching lines @@
 void IncidentReportingService::SetCollectEnvironmentHook(
     CollectEnvironmentDataFn collect_environment_data_hook,
     const scoped_refptr<base::TaskRunner>& task_runner) {
   if (collect_environment_data_hook) {
     collect_environment_data_fn_ = collect_environment_data_hook;
     environment_collection_task_runner_ = task_runner;
   } else {
     collect_environment_data_fn_ = &CollectEnvironmentData;
     environment_collection_task_runner_ =
         content::BrowserThread::GetBlockingPool()
-            ->GetTaskRunnerWithShutdownBehavior(
-                base::SequencedWorkerPool::SKIP_ON_SHUTDOWN);
+            ->GetTaskRunnerWithShutdownBehavior(GetShutdownBehavior());
   }
 }
 
 void IncidentReportingService::DoExtensionCollection(
     ClientIncidentReport_ExtensionData* extension_data) {
   CollectExtensionData(extension_data);
 }
 
 void IncidentReportingService::OnProfileAdded(Profile* profile) {
   DCHECK(thread_checker_.CalledOnValidThread());
@@ skipping 635 matching lines @@
       if (!profile->IsOffTheRecord())
         OnProfileDestroyed(profile);
       break;
     }
     default:
       break;
   }
 }
 
 }  // namespace safe_browsing