Added support for greylisting of system calls.

sandbox/linux/sandbox_linux.gypi

Index: sandbox/linux/sandbox_linux.gypi
diff --git a/sandbox/linux/sandbox_linux.gypi b/sandbox/linux/sandbox_linux.gypi
index c02cd3164423fdbbfc17c08b46d5bd16335b054c..535fb8921effeb7044128c645030fe7c80c7d7b0 100644
--- a/sandbox/linux/sandbox_linux.gypi
+++ b/sandbox/linux/sandbox_linux.gypi
@@ -58,6 +58,7 @@
             'seccomp-bpf/errorcode_unittest.cc',
             'seccomp-bpf/sandbox_bpf_unittest.cc',
             'seccomp-bpf/syscall_iterator_unittest.cc',
+            'seccomp-bpf/syscall_unittest.cc',
           ],
         }],
       ],
@@ -77,6 +78,8 @@
         'seccomp-bpf/instruction.h',
         'seccomp-bpf/sandbox_bpf.cc',
         'seccomp-bpf/sandbox_bpf.h',
+        'seccomp-bpf/syscall.cc',
+        'seccomp-bpf/syscall.h',
         'seccomp-bpf/syscall_iterator.cc',
         'seccomp-bpf/syscall_iterator.h',
         'seccomp-bpf/verifier.cc',