Exposed flags to the regex parser

javascript/extractor/src/com/semmle/js/parser/RegExpParser.java

@@ -67,6 +67,7 @@ public class RegExpParser {
   private List<Error> errors;
   private List<BackReference> backrefs;
   private int maxbackref;
+  private String flags;
 
   /** Parse the given string as a regular expression. */
   public Result parse(String src) {
@@ -82,6 +83,11 @@ public class RegExpParser {
     return new Result(root, errors);
   }
 
+  public Result parse(String src, String flags) {
+    this.flags = flags;
+    return parse(src);
+  }
+
   private static String fromCodePoint(int codepoint) {
     if (Character.isValidCodePoint(codepoint)) return new String(Character.toChars(codepoint));
     // replacement character