Split initialization_util into a Hermetic Library and a Variations Library

components/task_scheduler_util/initialization/browser_util.h

+// Copyright 2016 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 COMPONENTS_TASK_SCHEDULER_UTIL_INITIALIZATION_BROWSER_UTIL_H_
+#define COMPONENTS_TASK_SCHEDULER_UTIL_INITIALIZATION_BROWSER_UTIL_H_
+
+#include <vector>
+
+#include "base/task_scheduler/scheduler_worker_pool_params.h"
+#include "base/time/time.h"
+
+namespace base {
+class TaskTraits;
+}
+
+namespace task_scheduler_util {
+namespace initialization {
+
+enum WorkerPoolType : size_t {
+  BACKGROUND = 0,
+  BACKGROUND_FILE_IO,
+  FOREGROUND,
+  FOREGROUND_FILE_IO,
+  WORKER_POOL_COUNT  // Always last.
+};
+
+struct SingleWorkerPoolConfiguration {
+  base::SchedulerWorkerPoolParams::StandbyThreadPolicy standby_thread_policy;
+  int threads = 0;
+  base::TimeDelta detach_period;
+};
+
+struct BrowserWorkerPoolsConfiguration {
+  SingleWorkerPoolConfiguration background;
+  SingleWorkerPoolConfiguration background_file_io;
+  SingleWorkerPoolConfiguration foreground;
+  SingleWorkerPoolConfiguration foreground_file_io;
+};
+
+// Converts a BrowserWorkerPoolsConfiguration to a vector of
+// base::SchedulerWorkerPoolParams for consumption by task scheduler
+// initialization.
+std::vector<base::SchedulerWorkerPoolParams>
+BrowserWorkerPoolConfigurationToSchedulerWorkerPoolParams(
+    const BrowserWorkerPoolsConfiguration& config);
+
+// Maps |traits| to the index of a browser worker pool vector provided by
+// BrowserWorkerPoolConfigurationToSchedulerWorkerPoolParams() or
+// GetDefaultBrowserSchedulerWorkerPoolParams().
+size_t BrowserWorkerPoolIndexForTraits(const base::TaskTraits& traits);
+
+// Returns the default browser scheduler worker pool params.
+std::vector<base::SchedulerWorkerPoolParams>
+GetDefaultBrowserSchedulerWorkerPoolParams();
+
+}  // namespace initialization
+}  // namespace task_scheduler_util
+
+#endif  // COMPONENTS_TASK_SCHEDULER_UTIL_INITIALIZATION_BROWSER_UTIL_H_