Use TaskScheduler instead of blocking pool in external_metrics.cc.

chrome/browser/chromeos/external_metrics.cc

 // Copyright (c) 2012 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/external_metrics.h"
 
 #include <stddef.h>
 
 #include <map>
 #include <memory>
 #include <string>
 #include <vector>
 
 #include "base/bind.h"
 #include "base/metrics/histogram_macros.h"
 #include "base/metrics/sparse_histogram.h"
 #include "base/metrics/statistics_recorder.h"
 #include "base/metrics/user_metrics.h"
-#include "base/threading/sequenced_worker_pool.h"
+#include "base/task_scheduler/post_task.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/metrics/chromeos_metrics_provider.h"
 #include "components/metrics/metrics_service.h"
 #include "components/metrics/serialization/metric_sample.h"
 #include "components/metrics/serialization/serialization_utils.h"
 #include "content/public/browser/browser_thread.h"
 
 using content::BrowserThread;
 
 namespace chromeos {
@@ skipping 11 matching lines @@
       base::StatisticsRecorder::FindHistogram(name);
   if (!histogram)
     return true;
   return histogram->HasConstructionArguments(minimum, maximum, bucket_count);
 }
 
 bool CheckLinearValues(const std::string& name, int maximum) {
   return CheckValues(name, 1, maximum, maximum + 1);
 }
 
+// The interval between external metrics collections.
+constexpr base::TimeDelta kExternalMetricsCollectionInterval =
+    base::TimeDelta::FromSeconds(30);
+constexpr char kEventsFilePath[] = "/var/lib/metrics/uma-events";
+
 }  // namespace
 
-// The interval between external metrics collections in seconds
-static const int kExternalMetricsCollectionIntervalSeconds = 30;
-const char kEventsFilePath[] = "/var/lib/metrics/uma-events";
-
 ExternalMetrics::ExternalMetrics() : uma_events_file_(kEventsFilePath) {
 }
 
 ExternalMetrics::~ExternalMetrics() {}
 
 void ExternalMetrics::Start() {
   ScheduleCollector();
 }
 
 // static
@@ skipping 97 matching lines @@
 
   return samples.size();
 }
 
 void ExternalMetrics::CollectEventsAndReschedule() {
   CollectEvents();
   ScheduleCollector();
 }
 
 void ExternalMetrics::ScheduleCollector() {
-  bool result = BrowserThread::GetBlockingPool()->PostDelayedWorkerTask(
+  base::PostDelayedTaskWithTraits(
       FROM_HERE,
-      base::Bind(&chromeos::ExternalMetrics::CollectEventsAndReschedule, this),
-      base::TimeDelta::FromSeconds(kExternalMetricsCollectionIntervalSeconds));
-  DCHECK(result);
+      base::TaskTraits().MayBlock().WithPriority(
+          base::TaskPriority::BACKGROUND),
+      base::BindOnce(&chromeos::ExternalMetrics::CollectEventsAndReschedule,
+                     this),
+      kExternalMetricsCollectionInterval);
 }
 
 }  // namespace chromeos