Disable BaselinePolicy.SIGSYS_InvalidSyscall on Chrome OS.

BUG=424973
TEST=chromeos=1 compile,
TEST=out_chromeos/Debug/sandbox_linux_unittests --gtest_filter=*SIGSYS_InvalidSyscall*
...
0 tests run

R=mdempsky@chromium.org

Review URL: https://codereview.chromium.org/646853005

Cr-Commit-Position: refs/heads/master@{#300299}

sandbox/linux/seccomp-bpf-helpers/baseline_policy_unittest.cc

@@ -213,12 +213,15 @@ BPF_TEST_C(BaselinePolicy, EPERM_getcwd, BaselinePolicy) {
   BPF_ASSERT_EQ(EPERM, errno);
 }
 
+// TODO(jorgelo): re-enable this after crbug.com/424973 is fixed.
+#if !defined(OS_CHROMEOS)
 BPF_DEATH_TEST_C(BaselinePolicy,
                  SIGSYS_InvalidSyscall,
                  DEATH_SEGV_MESSAGE(GetErrorMessageContentForTests()),
                  BaselinePolicy) {
   Syscall::InvalidCall();
 }
+#endif
 
 // A failing test using this macro could be problematic since we perform
 // system calls by passing "0" as every argument.