Revert "Hack around TLS destructors firing after the process exits"

runtime/vm/thread_interrupter.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/thread_interrupter.h"
 
 #include "vm/flags.h"
 #include "vm/lockers.h"
 #include "vm/os.h"
 #include "vm/simulator.h"
@@ skipping 94 matching lines @@
   // Join the thread.
   ASSERT(interrupter_thread_id_ != OSThread::kInvalidThreadJoinId);
   OSThread::Join(interrupter_thread_id_);
   interrupter_thread_id_ = OSThread::kInvalidThreadJoinId;
 
   if (FLAG_trace_thread_interrupter) {
     OS::Print("ThreadInterrupter shut down.\n");
   }
 }
 
-
 // Delay between interrupts.
 void ThreadInterrupter::SetInterruptPeriod(intptr_t period) {
   if (shutdown_) {
     return;
   }
   ASSERT(initialized_);
   ASSERT(period > 0);
   interrupt_period_ = period;
 }
 
@@ skipping 93 matching lines @@
   }
   {
     // Signal to main thread we are exiting.
     MonitorLocker shutdown_ml(monitor_);
     thread_running_ = false;
     shutdown_ml.Notify();
   }
 }
 
 }  // namespace dart