NaCl: Clean up file descriptor setup in nacl_helper on linux

chrome/nacl/nacl_helper_linux.cc

Index: chrome/nacl/nacl_helper_linux.cc
diff --git a/chrome/nacl/nacl_helper_linux.cc b/chrome/nacl/nacl_helper_linux.cc
index a5cb131241f09250066e5780291398d18a0266e3..3c6fb8ff56166b333e458296b7199a23e36ddd4a 100644
--- a/chrome/nacl/nacl_helper_linux.cc
+++ b/chrome/nacl/nacl_helper_linux.cc
@@ -43,14 +43,8 @@ void BecomeNaClLoader(const std::vector<int>& child_fds,
   // don't need zygote FD any more
   if (HANDLE_EINTR(close(kNaClZygoteDescriptor)) != 0)
     LOG(ERROR) << "close(kNaClZygoteDescriptor) failed.";
-  // Set up browser descriptor on fd 3 and IPC as expected by Chrome.
   base::GlobalDescriptors::GetInstance()->Set(kPrimaryIPCChannel,
-      kPrimaryIPCChannel + base::GlobalDescriptors::kBaseDescriptor);
-  int zfd = dup2(child_fds[kNaClBrowserFDIndex], kNaClBrowserDescriptor);
-  if (zfd != kNaClBrowserDescriptor) {
-    LOG(ERROR) << "Could not initialize kNaClBrowserDescriptor";
-    _exit(-1);
-  }
+                                              child_fds[kNaClBrowserFDIndex]);
 
   MessageLoopForIO main_message_loop;
   NaClListener listener;