Always Ignore SIGPIPE for NaCl both in SFI mode and non SFI mode.

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 e170c526da5b2dcd302a5e17c83b05f6d4432a7d..8c042d02688e6a039b5d565f8e43eb138e00917f 100644
--- a/components/nacl/loader/nacl_helper_linux.cc
+++ b/components/nacl/loader/nacl_helper_linux.cc
@@ -91,6 +91,11 @@ void BecomeNaClLoader(base::ScopedFD browser_fd,
     nacl::nonsfi::InitializeSignalHandler();
   }
 
+  // Always ignore SIGPIPE, for consistency with other Chrome processes and
+  // because some IPC code, such as sync_socket_posix.cc, requires this.
+  // We do this before seccomp-bpf is initialized.
+  PCHECK(signal(SIGPIPE, SIG_IGN) != SIG_ERR);
+
   // Finish layer-1 sandbox initialization and initialize the layer-2 sandbox.
   CHECK(!nacl_sandbox->HasOpenDirectory());
   nacl_sandbox->InitializeLayerTwoSandbox(uses_nonsfi_mode);