Replace PluginThreadTaskRunner with a simpler MainPluginThreadTaskRunner.

remoting/client/plugin/pepper_main_thread_task_runner.h

+// 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.
+
+#ifndef REMOTING_CLIENT_PLUGIN_PEPPER_MAIN_THREAD_TASK_RUNNER_H_
+#define REMOTING_CLIENT_PLUGIN_PEPPER_MAIN_THREAD_TASK_RUNNER_H_
+
+#include "base/callback_forward.h"
+#include "base/compiler_specific.h"
+#include "base/macros.h"
+#include "base/single_thread_task_runner.h"
+#include "base/time/time.h"
+#include "ppapi/utility/completion_callback_factory.h"
+
+namespace pp {
+class Core;
+}  // namespace pp
+
+namespace remoting {
+
+// SingleThreadTaskRunner implementation for the main plugin thread.
+class PepperMainThreadTaskRunner : public base::SingleThreadTaskRunner {
+ public:
+  PepperMainThreadTaskRunner();
+
+  // base::SingleThreadTaskRunner interface.
+  bool PostDelayedTask(const tracked_objects::Location& from_here,
+                       const base::Closure& task,
+                       base::TimeDelta delay) override;
+  bool PostNonNestableDelayedTask(const tracked_objects::Location& from_here,
+                                  const base::Closure& task,
+                                  base::TimeDelta delay) override;
+  bool RunsTasksOnCurrentThread() const override;
+
+ protected:
+  ~PepperMainThreadTaskRunner() override;
+
+ private:
+  // Helper that allows a base::Closure to be used as a pp::CompletionCallback,
+  // by ignoring the completion result.
+  void RunTask(int32_t result, const base::Closure& task);
+
+  pp::Core* core_;
+  pp::CompletionCallbackFactory<PepperMainThreadTaskRunner> callback_factory_;
+
+  DISALLOW_COPY_AND_ASSIGN(PepperMainThreadTaskRunner);
+};
+
+}  // namespace remoting
+
+#endif  // REMOTING_CLIENT_PLUGIN_PEPPER_MAIN_THREAD_TASK_RUNNER_H_