Use portable typedef for PIDs (process IDs).

base/process_win.cc

 // Copyright (c) 2006-2008 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.h"
 #include "base/logging.h"
 #include "base/process_util.h"
 #include "base/scoped_ptr.h"
 
 namespace base {
@@ skipping 89 matching lines @@
 }
 
 bool Process::EmptyWorkingSet() {
   if (!process_)
     return false;
 
   BOOL rv = SetProcessWorkingSetSize(process_, -1, -1);
   return rv == TRUE;
 }
 
-int32 Process::pid() const {
+ProcessId Process::pid() const {
   if (process_ == 0)
     return 0;
 
   return GetProcId(process_);
 }
 
 bool Process::is_current() const {
   return process_ == GetCurrentProcess();
 }
 
 // static
 Process Process::Current() {
   return Process(GetCurrentProcess());
 }
 
 }  // namespace base