* Irregexp: Handle backtrack past look-ahead.

src/parser.cc

Index: src/parser.cc
diff --git a/src/parser.cc b/src/parser.cc
index 3dc69855d6fa37894b503c5f88593993c2003e94..333f1c7af40ce25d9738d6434e355f70c6bab939 100644
--- a/src/parser.cc
+++ b/src/parser.cc
@@ -4149,7 +4149,10 @@ RegExpTree* RegExpParser::ParseGroup() {
   } else {
     ASSERT(type == '=' || type == '!');
     bool is_positive = (type == '=');
-    return new RegExpLookahead(body, is_positive);
+    return new RegExpLookahead(body,
+                               is_positive,
+                               end_capture_index - capture_index,
+                               capture_index);
   }
 }