Improve linearized pdf load/show time.

pdf/timer.h

Index: pdf/timer.h
diff --git a/pdf/timer.h b/pdf/timer.h
new file mode 100644
index 0000000000000000000000000000000000000000..c9fba9d5191e1cb70df8a732245301dfd85980e7
--- /dev/null
+++ b/pdf/timer.h
@@ -0,0 +1,52 @@
+// 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 {
+ 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();
+  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_