Move base::FreeDeleter into its own header.

base/process/process_info_mac.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/process/process_info.h"
 
 #include <stddef.h>
 #include <sys/sysctl.h>
 #include <sys/time.h>
 #include <unistd.h>
 
 #include "base/macros.h"
+#include "base/memory/free_deleter.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/time/time.h"
 
 namespace base {
 
 // static
 const Time CurrentProcessInfo::CreationTime() {
   int mib[] = { CTL_KERN, KERN_PROC, KERN_PROC_PID, getpid() };
   size_t len = 0;
   if (sysctl(mib, arraysize(mib), NULL, &len, NULL, 0) < 0)
     return Time();
 
   scoped_ptr<struct kinfo_proc, base::FreeDeleter>
       proc(static_cast<struct kinfo_proc*>(malloc(len)));
   if (sysctl(mib, arraysize(mib), proc.get(), &len, NULL, 0) < 0)
     return Time();
   return Time::FromTimeVal(proc->kp_proc.p_un.__p_starttime);
 }
 
 }  // namespace base