NaCl: Clean up file descriptor setup in nacl_helper on linux

chrome/app/nacl_fork_delegate_linux.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 "chrome/app/nacl_fork_delegate_linux.h"
 
 #include <signal.h>
 #include <stdlib.h>
 #include <sys/resource.h>
 #include <sys/socket.h>
@@ skipping 16 matching lines @@
 NaClForkDelegate::NaClForkDelegate()
     : status_(kNaClHelperUnused),
       fd_(-1) {}
 
 // Note these need to match up with their counterparts in nacl_helper_linux.c
 // and nacl_helper_bootstrap_linux.c.
 const char kNaClHelperReservedAtZero[] =
     "--reserved_at_zero=0xXXXXXXXXXXXXXXXX";
 const char kNaClHelperRDebug[] = "--r_debug=0xXXXXXXXXXXXXXXXX";
 
-void NaClForkDelegate::Init(const int browserdesc, const int sandboxdesc) {
+void NaClForkDelegate::Init(const int sandboxdesc) {
   VLOG(1) << "NaClForkDelegate::Init()";
   int fds[2];
 
-  // Confirm a couple hard-wired assumptions.
-  // The NaCl constants are from chrome/nacl/nacl_linux_helper.h
-  DCHECK(kNaClBrowserDescriptor == browserdesc);
+  // Confirm a hard-wired assumption.
+  // The NaCl constant is from chrome/nacl/nacl_linux_helper.h
   DCHECK(kNaClSandboxDescriptor == sandboxdesc);
 
   CHECK(socketpair(PF_UNIX, SOCK_SEQPACKET, 0, fds) == 0);
   base::FileHandleMappingVector fds_to_map;
   fds_to_map.push_back(std::make_pair(fds[1], kNaClZygoteDescriptor));
   fds_to_map.push_back(std::make_pair(sandboxdesc, kNaClSandboxDescriptor));
 
   status_ = kNaClHelperUnused;
   FilePath helper_exe;
   FilePath helper_bootstrap_exe;
@@ skipping 102 matching lines @@
 
 bool NaClForkDelegate::AckChild(const int fd,
                                 const std::string& channel_switch) {
   int nwritten = HANDLE_EINTR(write(fd, channel_switch.c_str(),
                                     channel_switch.length()));
   if (nwritten != static_cast<int>(channel_switch.length())) {
     return false;
   }
   return true;
 }