Lower the priority of environment and process data collection.

chrome/browser/safe_browsing/incident_reporting/environment_data_collection.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/environment_data_collection.h"
 
 #include <string>
 
+#include "base/bind.h"
+#include "base/callback_helpers.h"
 #include "base/cpu.h"
 #include "base/sys_info.h"
+#include "base/threading/platform_thread.h"
+#include "base/threading/sequenced_worker_pool.h"
 #include "chrome/common/channel_info.h"
 #include "chrome/common/safe_browsing/csd.pb.h"
 #include "components/version_info/version_info.h"
 
 namespace safe_browsing {
 
 // Populates |process| with platform-specific data related to the chrome browser
 // process.
 void CollectPlatformProcessData(
     ClientIncidentReport_EnvironmentData_Process* process);
@@ skipping 34 matching lines @@
 
   process->set_chrome_update_channel(
       MapChannelToProtobuf(chrome::GetChannel()));
 
   CollectPlatformProcessData(process);
 }
 
 }  // namespace
 
 void CollectEnvironmentData(ClientIncidentReport_EnvironmentData* data) {
+  // Toggling priority only makes sense in a thread pool.
+  DCHECK(base::SequencedWorkerPool::GetWorkerPoolForCurrentThread());
+  // Reset priority when done with this task.
+  base::ScopedClosureRunner restore_priority(
+      base::Bind(&base::PlatformThread::SetCurrentThreadPriority,
+                 base::PlatformThread::GetCurrentThreadPriority()));
+  // Lower priority for this task.
+  base::PlatformThread::SetCurrentThreadPriority(
+      base::ThreadPriority::BACKGROUND);
+
   // OS
   {
     ClientIncidentReport_EnvironmentData_OS* os = data->mutable_os();
     os->set_os_name(base::SysInfo::OperatingSystemName());
     os->set_os_version(base::SysInfo::OperatingSystemVersion());
     CollectPlatformOSData(os);
   }
 
   // Machine
   {
@@ skipping 16 matching lines @@
   // implementations.
 }
 
 void CollectPlatformOSData(ClientIncidentReport_EnvironmentData_OS* os_data) {
   // Empty implementation for platforms that do not (yet) have their own
   // implementations.
 }
 #endif
 
 }  // namespace safe_browsing