Change single-interface mojo bindings to use SequencedTaskRunner.

mojo/public/cpp/bindings/tests/thread_per_task_sequenced_task_runner.h

+// Copyright 2017 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 MOJO_PUBLIC_CPP_BINDINGS_TESTS_THREAD_PER_TASK_SEQUENCED_TASK_RUNNER_H_
+#define MOJO_PUBLIC_CPP_BINDINGS_TESTS_THREAD_PER_TASK_SEQUENCED_TASK_RUNNER_H_
+
+#include "base/macros.h"
+#include "base/sequenced_task_runner.h"
+
+namespace mojo {
+namespace test {
+
+// Holds a base::SequencedTaskRunner implementation that runs each task on a
+// separate thread. Note that task delays are ignored and non-nestable tasks are
+// treated as nestable.
+class ThreadPerTaskSequencedTaskRunnerOwner {
+ public:
+  ThreadPerTaskSequencedTaskRunnerOwner();
+  ~ThreadPerTaskSequencedTaskRunnerOwner();
+
+  scoped_refptr<base::SequencedTaskRunner> GetSequencedTaskRunner();
+
+ private:
+  class TaskRunnerImpl;
+
+  scoped_refptr<TaskRunnerImpl> task_runner_;
+
+  DISALLOW_COPY_AND_ASSIGN(ThreadPerTaskSequencedTaskRunnerOwner);
+};
+
+}  // namespace test
+}  // namespace mojo
+
+#endif  // MOJO_PUBLIC_CPP_BINDINGS_TESTS_THREAD_PER_TASK_SEQUENCED_TASK_RUNNER_H_