Non-SFI mode: Use dummy PID for NaCl's IPC channel on Linux platform.

components/nacl/loader/nacl_helper_linux.cc

Index: components/nacl/loader/nacl_helper_linux.cc
diff --git a/components/nacl/loader/nacl_helper_linux.cc b/components/nacl/loader/nacl_helper_linux.cc
index d5b9fdf227ffccf7d095097b7182b131f265f355..8008e6b6f3e341bdf56f2ed01450fdc0cffa643e 100644
--- a/components/nacl/loader/nacl_helper_linux.cc
+++ b/components/nacl/loader/nacl_helper_linux.cc
@@ -48,6 +48,7 @@
 #include "content/public/common/content_descriptors.h"
 #include "content/public/common/zygote_fork_delegate_linux.h"
 #include "crypto/nss_util.h"
+#include "ipc/ipc_channel.h"
 #include "ipc/ipc_descriptors.h"
 #include "ipc/ipc_switches.h"
 #include "sandbox/linux/services/libc_urandom_override.h"
@@ -407,6 +408,7 @@ int main(int argc, char* argv[]) {
   // Now do nothing in main for nacl_helper_nonsfi.
 #if !defined(__native_client_nonsfi__)
   CommandLine::Init(argc, argv);
+  IPC::Channel::SetGlobalPid(-1);  // Set dummy PID for IPC.
   base::AtExitManager exit_manager;
   base::RandUint64();  // acquire /dev/urandom fd before sandbox is raised
   // Allows NSS to fopen() /dev/urandom.