Update from https://crrev.com/320343

sandbox/linux/seccomp-bpf/sandbox_bpf.cc

Index: sandbox/linux/seccomp-bpf/sandbox_bpf.cc
diff --git a/sandbox/linux/seccomp-bpf/sandbox_bpf.cc b/sandbox/linux/seccomp-bpf/sandbox_bpf.cc
index b6553d7e24da4fac9a63fe3b77095eb6cf8d9850..c96642ec408685548d96f056731469bc4844a0dc 100644
--- a/sandbox/linux/seccomp-bpf/sandbox_bpf.cc
+++ b/sandbox/linux/seccomp-bpf/sandbox_bpf.cc
@@ -24,16 +24,13 @@
 #include "base/posix/eintr_wrapper.h"
 #include "base/third_party/valgrind/valgrind.h"
 #include "sandbox/linux/bpf_dsl/codegen.h"
-#include "sandbox/linux/bpf_dsl/dump_bpf.h"
 #include "sandbox/linux/bpf_dsl/policy.h"
 #include "sandbox/linux/bpf_dsl/policy_compiler.h"
 #include "sandbox/linux/bpf_dsl/seccomp_macros.h"
 #include "sandbox/linux/bpf_dsl/syscall_set.h"
 #include "sandbox/linux/seccomp-bpf/die.h"
-#include "sandbox/linux/seccomp-bpf/errorcode.h"
 #include "sandbox/linux/seccomp-bpf/syscall.h"
 #include "sandbox/linux/seccomp-bpf/trap.h"
-#include "sandbox/linux/seccomp-bpf/verifier.h"
 #include "sandbox/linux/services/proc_util.h"
 #include "sandbox/linux/services/syscall_wrappers.h"
 #include "sandbox/linux/services/thread_helpers.h"
@@ -79,6 +76,14 @@ bool KernelSupportsSeccompTsync() {
   }
 }
 
+uint64_t EscapePC() {
+  intptr_t rv = Syscall::Call(-1);
+  if (rv == -1 && errno == ENOSYS) {
+    return 0;
+  }
+  return static_cast<uint64_t>(static_cast<uintptr_t>(rv));
+}
+
 }  // namespace
 
 SandboxBPF::SandboxBPF(bpf_dsl::Policy* policy)
@@ -184,25 +189,12 @@ scoped_ptr<CodeGen::Program> SandboxBPF::AssembleFilter(
   force_verification = true;
 #endif
   DCHECK(policy_);
+
   bpf_dsl::PolicyCompiler compiler(policy_.get(), Trap::Registry());
-  scoped_ptr<CodeGen::Program> program = compiler.Compile();
-
-  // Make sure compilation resulted in a BPF program that executes
-  // correctly. Otherwise, there is an internal error in our BPF compiler.
-  // There is really nothing the caller can do until the bug is fixed.
-  if (force_verification) {
-    // Verification is expensive. We only perform this step, if we are
-    // compiled in debug mode, or if the caller explicitly requested
-    // verification.
-
-    const char* err = NULL;
-    if (!Verifier::VerifyBPF(&compiler, *program, *policy_, &err)) {
-      bpf_dsl::DumpBPF::PrintProgram(*program);
-      SANDBOX_DIE(err);
-    }
+  if (Trap::SandboxDebuggingAllowedByUser()) {
+    compiler.DangerousSetEscapePC(EscapePC());
   }
-
-  return program.Pass();
+  return compiler.Compile(force_verification);
 }
 
 void SandboxBPF::InstallFilter(bool must_sync_threads) {