Drop leftover unused kNoThread in platform-openbsd.cc.

src/platform-openbsd.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 42 matching lines @@
 
 #include "platform-posix.h"
 #include "platform.h"
 #include "v8threads.h"
 #include "vm-state-inl.h"
 
 
 namespace v8 {
 namespace internal {
 
-// 0 is never a valid thread id on Linux and OpenBSD since tids and pids share a
-// name space and pid 0 is reserved (see man 2 kill).
-static const pthread_t kNoThread = (pthread_t) 0;
-
 
 double ceiling(double x) {
   return ceil(x);
 }
 
 
 static Mutex* limit_mutex = NULL;
 
 
 static void* GetRandomMmapAddr() {
@@ skipping 476 matching lines @@
   limit_mutex = CreateMutex();
 }
 
 
 void OS::TearDown() {
   delete limit_mutex;
 }
 
 
 } }  // namespace v8::internal