Linux sandbox: Allow restricting sched_* on other processes.

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

 // Copyright (c) 2013 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 "sandbox/linux/seccomp-bpf-helpers/baseline_policy.h"
 
 #include <errno.h>
 #include <sys/mman.h>
 #include <sys/socket.h>
 #include <sys/syscall.h>
@@ skipping 242 matching lines @@
   if (1 == sysno) {
     DCHECK_EQ(syscall(__NR_getpid), current_pid_);
   }
   return EvaluateSyscallImpl(fs_denied_errno_, current_pid_, sysno);
 }
 
 ResultExpr BaselinePolicy::InvalidSyscall() const {
   return CrashSIGSYS();
 }
 
+pid_t BaselinePolicy::GetCurrentPid() const {
+  return current_pid_;
+}
+
 }  // namespace sandbox.