Fix sandbox_bpf_unittest compile on ARM

sandbox/linux/seccomp-bpf/sandbox_bpf_unittest.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <ostream>
 
 #include "sandbox/linux/seccomp-bpf/bpf_tests.h"
 #include "sandbox/linux/seccomp-bpf/verifier.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
@@ skipping 139 matching lines @@
 ErrorCode SyntheticPolicy(int sysno) {
   if (sysno < static_cast<int>(MIN_SYSCALL) ||
       sysno > static_cast<int>(MAX_SYSCALL)) {
     // FIXME: we should really not have to do that in a trivial policy.
     return ErrorCode(ENOSYS);
   }
 
   // TODO(jorgelo): remove this restriction once crbug.com/141694 is fixed.
 #if defined(__arm__)
   if (sysno > kArmPublicSysnoCeiling)
-    return ENOSYS;
+    return ErrorCode(ENOSYS);
 #endif
 
   // TODO(markus): allow calls to write(). This should start working as soon
   //   as we switch to the new code generator. Currently we are blowing up,
   //   because our jumptable is getting too big.
   if (sysno == __NR_exit_group /* || sysno == __NR_write */) {
     // exit_group() is special, we really need it to work.
     // write() is needed for BPF_ASSERT() to report a useful error message.
     return ErrorCode(ErrorCode::ERR_ALLOWED);
   } else {
@@ skipping 23 matching lines @@
       // exit_group() is special
       continue;
     }
     errno = 0;
     BPF_ASSERT(syscall(syscall_number) == -1);
     BPF_ASSERT(errno == SysnoToRandomErrno(syscall_number));
   }
 }
 
 } // namespace