[Mac] In PlatformThread::CurrentId(), use pthread_self() instead of mach_thread_self().

base/threading/platform_thread_posix.cc

 // Copyright (c) 2012 The Chromium 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 "base/threading/platform_thread.h"
 
 #include <errno.h>
 #include <sched.h>
 
 #include "base/lazy_instance.h"
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/safe_strerror_posix.h"
 #include "base/threading/thread_local.h"
 #include "base/threading/thread_restrictions.h"
 #include "base/tracked_objects.h"
 
 #if defined(OS_MACOSX)
-#include <mach/mach.h>
 #include <sys/resource.h>
 #include <algorithm>
 #endif
 
 #if defined(OS_LINUX)
 #include <sys/prctl.h>
 #include <sys/syscall.h>
 #include <unistd.h>
 #endif
 
@@ skipping 95 matching lines @@
     delete params;
   return success;
 }
 
 }  // namespace
 
 // static
 PlatformThreadId PlatformThread::CurrentId() {
   // Pthreads doesn't have the concept of a thread ID, so we have to reach down
   // into the kernel.
-#if defined(OS_MACOSX)
-  mach_port_t port = mach_thread_self();
-  mach_port_deallocate(mach_task_self(), port);
-  return port;
-#elif defined(OS_LINUX)
+#if defined(OS_LINUX)
   return syscall(__NR_gettid);
 #elif defined(OS_ANDROID)
   return gettid();
 #elif defined(OS_NACL) || defined(OS_SOLARIS)
   return pthread_self();
 #elif defined(OS_POSIX)
   return reinterpret_cast<int64>(pthread_self());
 #endif
 }
 
@@ skipping 102 matching lines @@
 // Mac OS X uses lower-level mach APIs
 
 // static
 void PlatformThread::SetThreadPriority(PlatformThreadHandle, ThreadPriority) {
   // TODO(crogers): implement
   NOTIMPLEMENTED();
 }
 #endif
 
 }  // namespace base