mac/linux: rework plugin channel file descriptor creation

chrome/common/ipc_message.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 "chrome/common/ipc_message.h"
 
 #include "base/logging.h"
 #include "build/build_config.h"
 
 #if defined(OS_POSIX)
@@ skipping 91 matching lines @@
                                 base::FileDescriptor* descriptor) const {
   int descriptor_index;
   if (!ReadInt(iter, &descriptor_index))
     return false;
 
   FileDescriptorSet* file_descriptor_set = file_descriptor_set_.get();
   if (!file_descriptor_set)
     return false;
 
   descriptor->fd = file_descriptor_set->GetDescriptorAt(descriptor_index);
-  descriptor->auto_close = false;
+  descriptor->auto_close = true;
 
   return descriptor->fd >= 0;
 }
 
 void Message::EnsureFileDescriptorSet() {
   if (file_descriptor_set_.get() == NULL)
     file_descriptor_set_ = new FileDescriptorSet;
 }
 
 #endif
 
 }  // namespace IPC