Resynchronize timers if the Windows system time was changed.

src/platform-win32.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 444 matching lines @@
   TimeStamp time_now;
   GetSystemTimeAsFileTime(&time_now.ft_);
   DWORD ticks_now = timeGetTime();
 
   // Check if we need to resync due to clock rollover.
   needs_resync |= ticks_now < init_ticks;
 
   // Check if we need to resync due to elapsed time.
   needs_resync |= (time_now.t_ - init_time.t_) > kMaxClockElapsedTime;
 
+  // Check if we need to resync due to backwards time change.
+  needs_resync |= time_now.t_ < init_time.t_;
+
   // Resync the clock if necessary.
   if (needs_resync) {
     GetSystemTimeAsFileTime(&init_time.ft_);
     init_ticks = ticks_now = timeGetTime();
     initialized = true;
   }
 
   // Finally, compute the actual time.  Why is this so hard.
   DWORD elapsed = ticks_now - init_ticks;
   this->time_.t_ = init_time.t_ + (static_cast<int64_t>(elapsed) * 10000);
@@ skipping 1609 matching lines @@
 
 
 void Sampler::Stop() {
   ASSERT(IsActive());
   SamplerThread::RemoveActiveSampler(this);
   SetActive(false);
 }
 
 
 } }  // namespace v8::internal