Fix race condition in EventTimerPosix

webrtc/system_wrappers/source/event_timer_posix.h

 /*
  *  Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 19 matching lines @@
   EventTimerPosix();
   ~EventTimerPosix() override;
 
   EventTypeWrapper Wait(unsigned long max_time) override;
   bool Set() override;
 
   bool StartTimer(bool periodic, unsigned long time) override;
   bool StopTimer() override;
 
  private:
+  friend class EventTimerPosixTest;
+
   static bool Run(void* obj);
   bool Process();
-  EventTypeWrapper Wait(timespec* end_at);
+  EventTypeWrapper Wait(timespec* end_at, bool reset_state);
 
- private:
+  virtual rtc::PlatformThread* CreateThread();
+
   pthread_cond_t  cond_;
   pthread_mutex_t mutex_;
   bool event_set_;
 
   // TODO(pbos): Remove scoped_ptr and use PlatformThread directly.
   rtc::scoped_ptr<rtc::PlatformThread> timer_thread_;
   rtc::scoped_ptr<EventTimerPosix> timer_event_;
   timespec       created_at_;
 
   bool          periodic_;
-  unsigned long time_;  // In ms
+  unsigned long time_ms_;
   unsigned long count_;
+  bool is_stopping_;
 };
 
 }  // namespace webrtc
 
 #endif  // WEBRTC_SYSTEM_WRAPPERS_SOURCE_EVENT_POSIX_H_