Revert of Update re2

third_party/re2/util/thread.cc

 // Copyright 2009 The RE2 Authors.  All Rights Reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+#include <pthread.h>
+
+#include "util/util.h"
 #include "util/thread.h"
-#include "util/util.h"
 
 Thread::Thread() {
   pid_ = 0;
   running_ = 0;
   joinable_ = 0;
 }
 
 Thread::~Thread() {
 }
 
@@ skipping 16 matching lines @@
   CHECK(joinable_);
   void *val;
   pthread_join(pid_, &val);
   running_ = 0;
 }
 
 void Thread::SetJoinable(bool j) {
   CHECK(!running_);
   joinable_ = j;
 }