SyscallIterator: support C++11 range-based for loops

sandbox/linux/bpf_dsl/policy_compiler.cc

Index: sandbox/linux/bpf_dsl/policy_compiler.cc
diff --git a/sandbox/linux/bpf_dsl/policy_compiler.cc b/sandbox/linux/bpf_dsl/policy_compiler.cc
index ad100f957994227095aa3458fbd1b4a5b3f40a8f..f0e357a044db9b87026c7c1de5ee39c8b5df3c21 100644
--- a/sandbox/linux/bpf_dsl/policy_compiler.cc
+++ b/sandbox/linux/bpf_dsl/policy_compiler.cc
@@ -76,8 +76,7 @@ intptr_t BPFFailure(const struct arch_seccomp_data&, void* aux) {
 }
 
 bool HasUnsafeTraps(const SandboxBPFDSLPolicy* policy) {
-  for (SyscallIterator iter(false); !iter.Done();) {
-    uint32_t sysnum = iter.Next();
+  for (uint32_t sysnum : SyscallSet::ALL) {
     if (SyscallIterator::IsValid(sysnum) &&
         policy->EvaluateSyscall(sysnum)->HasUnsafeTraps()) {
       return true;
@@ -89,8 +88,8 @@ bool HasUnsafeTraps(const SandboxBPFDSLPolicy* policy) {
 }  // namespace
 
 struct PolicyCompiler::Range {
-  Range(uint32_t f, uint32_t t, const ErrorCode& e) : from(f), to(t), err(e) {}
-  uint32_t from, to;
+  Range(uint32_t f, const ErrorCode& e) : from(f), err(e) {}
+  uint32_t from;
   ErrorCode err;
 };
 
@@ -256,18 +255,18 @@ void PolicyCompiler::FindRanges(Ranges* ranges) {
                           ? policy_->EvaluateSyscall(old_sysnum)->Compile(this)
                           : invalid_err;
 
-  for (SyscallIterator iter(false); !iter.Done();) {
-    uint32_t sysnum = iter.Next();
+  for (uint32_t sysnum : SyscallSet::ALL) {
     ErrorCode err =
         SyscallIterator::IsValid(sysnum)
             ? policy_->EvaluateSyscall(static_cast<int>(sysnum))->Compile(this)
             : invalid_err;
-    if (!err.Equals(old_err) || iter.Done()) {
-      ranges->push_back(Range(old_sysnum, sysnum - 1, old_err));
+    if (!err.Equals(old_err)) {
+      ranges->push_back(Range(old_sysnum, old_err));
       old_sysnum = sysnum;
       old_err = err;
     }
   }
+  ranges->push_back(Range(old_sysnum, old_err));
 }
 
 Instruction* PolicyCompiler::AssembleJumpTable(Ranges::const_iterator start,