Use TaskScheduler::InitParams to initialize TaskScheduler in web_main_loop.mm.

ios/web/app/web_main_loop.mm

 // 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 "ios/web/app/web_main_loop.h"
 
 #include <stddef.h>
 
 #include <utility>
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/logging.h"
 #include "base/message_loop/message_loop.h"
 #include "base/metrics/histogram_macros.h"
 #include "base/path_service.h"
 #include "base/power_monitor/power_monitor.h"
 #include "base/power_monitor/power_monitor_device_source.h"
 #include "base/process/process_metrics.h"
 #include "base/system_monitor/system_monitor.h"
 #include "base/task_scheduler/initialization_util.h"
 #include "base/task_scheduler/scheduler_worker_pool_params.h"
 #include "base/task_scheduler/task_scheduler.h"
-#include "base/task_scheduler/task_traits.h"
 #include "base/threading/thread_restrictions.h"
 #import "ios/web/net/cookie_notification_bridge.h"
 #include "ios/web/public/app/web_main_parts.h"
 #import "ios/web/public/web_client.h"
 #include "ios/web/web_thread_impl.h"
 #include "ios/web/webui/url_data_manager_ios.h"
 #include "net/base/network_change_notifier.h"
 
 #if !defined(__has_feature) || !__has_feature(objc_arc)
 #error "This file requires ARC support."
 #endif
 
 namespace web {
 
 namespace {
 
-enum WorkerPoolType : size_t {
-  BACKGROUND = 0,
-  BACKGROUND_BLOCKING,
-  FOREGROUND,
-  FOREGROUND_BLOCKING,
-  WORKER_POOL_COUNT  // Always last.
-};
-
-std::vector<base::SchedulerWorkerPoolParams>
-GetDefaultSchedulerWorkerPoolParams() {
+std::unique_ptr<base::TaskScheduler::InitParams>
+GetDefaultTaskSchedulerInitParams() {
   using StandbyThreadPolicy =
       base::SchedulerWorkerPoolParams::StandbyThreadPolicy;
-  using ThreadPriority = base::ThreadPriority;
-  std::vector<base::SchedulerWorkerPoolParams> params_vector;
-  params_vector.emplace_back(
-      "Background", ThreadPriority::BACKGROUND, StandbyThreadPolicy::ONE,
-      base::RecommendedMaxNumberOfThreadsInPool(2, 8, 0.1, 0),
-      base::TimeDelta::FromSeconds(30));
-  params_vector.emplace_back(
-      "BackgroundBlocking", ThreadPriority::BACKGROUND,
-      StandbyThreadPolicy::ONE,
-      base::RecommendedMaxNumberOfThreadsInPool(2, 8, 0.1, 0),
-      base::TimeDelta::FromSeconds(30));
-  params_vector.emplace_back(
-      "Foreground", ThreadPriority::NORMAL, StandbyThreadPolicy::ONE,
-      base::RecommendedMaxNumberOfThreadsInPool(3, 8, 0.3, 0),
-      base::TimeDelta::FromSeconds(30));
-  params_vector.emplace_back(
-      "ForegroundBlocking", ThreadPriority::NORMAL, StandbyThreadPolicy::ONE,
-      base::RecommendedMaxNumberOfThreadsInPool(3, 8, 0.3, 0),
-      base::TimeDelta::FromSeconds(30));
-  DCHECK_EQ(WORKER_POOL_COUNT, params_vector.size());
-  return params_vector;
-}
-
-// Returns the worker pool index for |traits| defaulting to FOREGROUND or
-// FOREGROUND_BLOCKING on any other priorities based off of worker pools defined
-// in GetDefaultSchedulerWorkerPoolParams().
-size_t DefaultBrowserWorkerPoolIndexForTraits(const base::TaskTraits& traits) {
-  const bool is_background =
-      traits.priority() == base::TaskPriority::BACKGROUND;
-  if (traits.may_block() || traits.with_base_sync_primitives())
-    return is_background ? BACKGROUND_BLOCKING : FOREGROUND_BLOCKING;
-
-  return is_background ? BACKGROUND : FOREGROUND;
+  return base::MakeUnique<base::TaskScheduler::InitParams>(
+      base::SchedulerWorkerPoolParams(
+          StandbyThreadPolicy::ONE,
+          base::RecommendedMaxNumberOfThreadsInPool(2, 8, 0.1, 0),
+          base::TimeDelta::FromSeconds(30)),
+      base::SchedulerWorkerPoolParams(
+          StandbyThreadPolicy::ONE,
+          base::RecommendedMaxNumberOfThreadsInPool(2, 8, 0.1, 0),
+          base::TimeDelta::FromSeconds(30)),
+      base::SchedulerWorkerPoolParams(
+          StandbyThreadPolicy::ONE,
+          base::RecommendedMaxNumberOfThreadsInPool(3, 8, 0.3, 0),
+          base::TimeDelta::FromSeconds(30)),
+      base::SchedulerWorkerPoolParams(
+          StandbyThreadPolicy::ONE,
+          base::RecommendedMaxNumberOfThreadsInPool(3, 8, 0.3, 0),
+          base::TimeDelta::FromSeconds(30)));
 }
 
 }  // namespace
 
 // The currently-running WebMainLoop.  There can be one or zero.
 // TODO(rohitrao): Desktop uses this to implement
 // ImmediateShutdownAndExitProcess.  If we don't need that functionality, we can
 // remove this.
 WebMainLoop* g_current_web_main_loop = nullptr;
 
@@ skipping 67 matching lines @@
 
 int WebMainLoop::PreCreateThreads() {
   if (parts_) {
     parts_->PreCreateThreads();
   }
 
   return result_code_;
 }
 
 int WebMainLoop::CreateThreads() {
-  std::vector<base::SchedulerWorkerPoolParams> params_vector;
-  base::TaskScheduler::WorkerPoolIndexForTraitsCallback
-      index_to_traits_callback;
-  GetWebClient()->GetTaskSchedulerInitializationParams(
-      &params_vector, &index_to_traits_callback);
-
-  if (params_vector.empty() || index_to_traits_callback.is_null()) {
-    params_vector = GetDefaultSchedulerWorkerPoolParams();
-    index_to_traits_callback =
-        base::Bind(&DefaultBrowserWorkerPoolIndexForTraits);
-  }
+  auto task_scheduler_init_params =
+      GetWebClient()->GetTaskSchedulerInitParams();
+  if (!task_scheduler_init_params)
+    task_scheduler_init_params = GetDefaultTaskSchedulerInitParams();
+  DCHECK(task_scheduler_init_params);
 
   base::TaskScheduler::CreateAndSetDefaultTaskScheduler(
-      params_vector, index_to_traits_callback);
+      "", *task_scheduler_init_params.get());
 
   GetWebClient()->PerformExperimentalTaskSchedulerRedirections();
 
   base::Thread::Options io_message_loop_options;
   io_message_loop_options.message_loop_type = base::MessageLoop::TYPE_IO;
 
   // Start threads in the order they occur in the WebThread::ID
   // enumeration, except for WebThread::UI which is the main
   // thread.
   //
@@ skipping 140 matching lines @@
   main_thread_.reset(
       new WebThreadImpl(WebThread::UI, base::MessageLoop::current()));
 }
 
 int WebMainLoop::WebThreadsStarted() {
   cookie_notification_bridge_.reset(new CookieNotificationBridge);
   return result_code_;
 }
 
 }  // namespace web