Replace PluginThreadTaskRunner with a simpler MainPluginThreadTaskRunner.

remoting/client/plugin/pepper_main_thread_task_runner.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 "remoting/client/plugin/pepper_main_thread_task_runner.h"
+
+#include "base/bind.h"
+#include "ppapi/cpp/core.h"
+
+namespace remoting {
+
+PepperMainThreadTaskRunner::PepperMainThreadTaskRunner()
+    : core_(pp::Module::Get()->core()), callback_factory_(this) {}
+
+bool PepperMainThreadTaskRunner::PostDelayedTask(
+    const tracked_objects::Location& from_here,
+    const base::Closure& task,
+    base::TimeDelta delay) {
+  core_->CallOnMainThread(delay.InMillisecondsRoundedUp(),
+                          callback_factory_.NewCallback(
+                              &PepperMainThreadTaskRunner::RunTask, task));
+  return true;
+}
+
+bool PepperMainThreadTaskRunner::PostNonNestableDelayedTask(
+    const tracked_objects::Location& from_here,
+    const base::Closure& task,
+    base::TimeDelta delay) {
+  return PostDelayedTask(from_here, task, delay);
+}
+
+bool PepperMainThreadTaskRunner::RunsTasksOnCurrentThread() const {
+  return core_->IsMainThread();
+}
+
+PepperMainThreadTaskRunner::~PepperMainThreadTaskRunner() {}
+
+void PepperMainThreadTaskRunner::RunTask(int32_t result,
+                                         const base::Closure& task) {
+  task.Run();
+}
+
+}  // namespace remoting