Redirect the MessageLoop's task runner to the renderer scheduler

components/scheduler/child/scheduler_task_runner_delegate_impl.cc

+// Copyright 2015 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 "components/scheduler/child/scheduler_task_runner_delegate_impl.h"
+
+namespace scheduler {
+
+// static
+scoped_refptr<SchedulerTaskRunnerDelegateImpl>
+SchedulerTaskRunnerDelegateImpl::Create(base::MessageLoop* message_loop) {
+  return make_scoped_refptr(new SchedulerTaskRunnerDelegateImpl(message_loop));
+}
+
+SchedulerTaskRunnerDelegateImpl::SchedulerTaskRunnerDelegateImpl(
+    base::MessageLoop* message_loop)
+    : message_loop_(message_loop),
+      message_loop_task_runner_(message_loop->task_runner()) {}
+
+SchedulerTaskRunnerDelegateImpl::~SchedulerTaskRunnerDelegateImpl() {
+  RestoreDefaultTaskRunner();
+}
+
+void SchedulerTaskRunnerDelegateImpl::SetDefaultTaskRunner(
+    scoped_refptr<base::SingleThreadTaskRunner> task_runner) {
+  message_loop_->SetTaskRunner(task_runner);
+}
+
+void SchedulerTaskRunnerDelegateImpl::RestoreDefaultTaskRunner() {
+  if (base::MessageLoop::current() == message_loop_)
+    message_loop_->SetTaskRunner(message_loop_task_runner_);
+}
+
+bool SchedulerTaskRunnerDelegateImpl::PostDelayedTask(
+    const tracked_objects::Location& from_here,
+    const base::Closure& task,
+    base::TimeDelta delay) {
+  return message_loop_task_runner_->PostDelayedTask(from_here, task, delay);
+}
+
+bool SchedulerTaskRunnerDelegateImpl::PostNonNestableDelayedTask(
+    const tracked_objects::Location& from_here,
+    const base::Closure& task,
+    base::TimeDelta delay) {
+  return message_loop_task_runner_->PostNonNestableDelayedTask(from_here, task,
+                                                               delay);
+}
+
+bool SchedulerTaskRunnerDelegateImpl::RunsTasksOnCurrentThread() const {
+  return message_loop_task_runner_->RunsTasksOnCurrentThread();
+}
+
+bool SchedulerTaskRunnerDelegateImpl::IsNested() const {
+  return message_loop_->IsNested();
+}
+
+void SchedulerTaskRunnerDelegateImpl::AddTaskObserver(
+    base::MessageLoop::TaskObserver* task_observer) {
+  message_loop_->AddTaskObserver(task_observer);
+}
+
+void SchedulerTaskRunnerDelegateImpl::RemoveTaskObserver(
+    base::MessageLoop::TaskObserver* task_observer) {
+  message_loop_->RemoveTaskObserver(task_observer);
+}
+
+}  // namespace scheduler