GN: Build nacl_helper_nonsfi unit tests

components/nacl/loader/nonsfi/nonsfi_sandbox_unittest.cc

Index: components/nacl/loader/nonsfi/nonsfi_sandbox_unittest.cc
diff --git a/components/nacl/loader/nonsfi/nonsfi_sandbox_unittest.cc b/components/nacl/loader/nonsfi/nonsfi_sandbox_unittest.cc
index 85b94a8b18d3d2d169cbbf28b8af1d1e77d48593..8500a69a3d4114706929798746f45058c8b24d50 100644
--- a/components/nacl/loader/nonsfi/nonsfi_sandbox_unittest.cc
+++ b/components/nacl/loader/nonsfi/nonsfi_sandbox_unittest.cc
@@ -113,13 +113,6 @@ void DoPipe(base::ScopedFD* fds) {
   fds[1].reset(tmp_fds[1]);
 }
 
-void DoSocketpair(base::ScopedFD* fds) {

[Mark Seaborn, 2015/12/03 19:05:07]

Is removing this required because GN is compiling with different warnings? 
Please comment this part in the commit message.

[Petr Hosek, 2015/12/04 05:57:46]

Yes, this function is not being used which triggers a compilation error because
of -Wunused-function which is set by default in GN. I have added a comment into
the commit message.

-  int tmp_fds[2];
-  BPF_ASSERT_EQ(0, socketpair(AF_UNIX, SOCK_STREAM, 0, tmp_fds));
-  fds[0].reset(tmp_fds[0]);
-  fds[1].reset(tmp_fds[1]);
-}
-
 TEST(NaClNonSfiSandboxTest, BPFIsSupported) {
   bool seccomp_bpf_supported = sandbox::SandboxBPF::SupportsSeccompSandbox(
       sandbox::SandboxBPF::SeccompLevel::SINGLE_THREADED);