content: Add task queue manager

content/renderer/scheduler/task_queue_scheduler_default.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 "content/renderer/scheduler/task_queue_scheduler_default.h"
+
+namespace content {
+
+TaskQueueSchedulerDefault::TaskQueueSchedulerDefault() {
+}
+
+TaskQueueSchedulerDefault::~TaskQueueSchedulerDefault() {
+}
+
+void TaskQueueSchedulerDefault::DidQueueTask(TaskQueueManager::QueueId queue) {
+}
+
+void TaskQueueSchedulerDefault::SetWorkQueues(
+    const std::vector<const base::TaskQueue*>& work_queues) {
+  work_queues_ = work_queues;
+}
+
+bool TaskQueueSchedulerDefault::ShouldReloadWorkQueue(
+    TaskQueueManager::QueueId queue) {
+  return true;
+}
+
+bool TaskQueueSchedulerDefault::ChooseWorkQueueToService(
+    TaskQueueManager::QueueId* out_queue) {
+  DCHECK(work_queues_.size());
+  TaskQueueManager::QueueId chosen_queue = TaskQueueManager::kDefaultTaskQueue;
+  for (size_t i = 1; i < work_queues_.size(); i++) {
+    if (work_queues_[i]->empty())
+      continue;
+    if (work_queues_[chosen_queue]->empty() ||
+        work_queues_[i]->front() < work_queues_[chosen_queue]->front()) {
+      chosen_queue = static_cast<TaskQueueManager::QueueId>(i);
+    }
+  }
+  *out_queue = chosen_queue;
+  return true;
+}
+
+}  // namespace content