Improve linearized pdf load/show time.

pdf/timer.h

+// Copyright (c) 2016 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 PDF_TIMER_H_
+#define PDF_TIMER_H_
+
+#include <set>
+
+#include "base/macros.h"
+#include "ppapi/utility/completion_callback_factory.h"
+
+namespace chrome_pdf {
+
+class Timer {

[Lei Zhang, 2016/10/05 07:18:08]

I only see one class inherit from Timer. Is it going to get reused and/or is it
important enough that you want to keep it separate?

[snake, 2016/10/05 14:14:10]

I want reuse it in next CLs for PDF plugin.

+ public:
+  explicit Timer(int delay);
+  virtual ~Timer();
+
+  virtual void OnTimer() = 0;
+
+ private:
+  friend class TestTimerRunner;
+  void PostCallback();
+  void TimerProc(int32_t result);
+
+  int delay_;
+  pp::CompletionCallbackFactory<Timer> callback_factory_;
+
+  DISALLOW_COPY_AND_ASSIGN(Timer);
+};
+
+class TestTimerRunner {
+ public:
+  TestTimerRunner();

[Lei Zhang, 2016/10/05 07:18:08]

I don't see this class getting instantiated anywhere.

[snake, 2016/10/05 14:14:10]

This will be needs for tests in next CLs.

[Lei Zhang, 2016/10/21 09:33:08]

So can you add this in the next CL, when it is needed?

Also, do you really need a new Timer class? There already exists base::Timer and
base::MockTimer.

+  virtual ~TestTimerRunner();
+
+  void RunUntilIdle();
+  void RunScheduled();
+  int scheduled_count() const;
+  void RegisterTimer(Timer* timer);
+  void UnregisterTimer(Timer* timer);
+
+ private:
+  std::set<Timer*> scheduled_timers_;
+
+  DISALLOW_COPY_AND_ASSIGN(TestTimerRunner);
+};
+
+}  // namespace chrome_pdf
+
+#endif  // PDF_TIMER_H_