Prevent read-after-buffer in SourcePositionTableIterator::Advance.

src/source-position-table.cc

Index: src/source-position-table.cc
diff --git a/src/source-position-table.cc b/src/source-position-table.cc
index 845081b711163e472e96dd24f50aaaf1e6f69344..35d8e7c2f6806fbf00ae7e934e354c982c35bb82 100644
--- a/src/source-position-table.cc
+++ b/src/source-position-table.cc
@@ -175,7 +175,7 @@ SourcePositionTableIterator::SourcePositionTableIterator(ByteArray* byte_array)
 void SourcePositionTableIterator::Advance() {
   DCHECK(!done());
   DCHECK(index_ >= 0 && index_ <= table_->length());
-  if (index_ == table_->length()) {
+  if (index_ >= table_->length()) {
     index_ = kDone;
   } else {
     PositionTableEntry tmp;