Update charted to 0.4.8 and roll

packages/petitparser/lib/src/reflection/iterable.dart

-part of petitparser.reflection;
-
-/// Returns a lazy iterable over all parsers reachable from a [root].
-///
-/// For example, the following code prints the two parsers of the
-/// defined grammar:
-///
-///     var parser = range('0', '9').star();
-///     allParser(parser).forEach((each) {
-///       print(each);
-///     });
-///
-Iterable<Parser> allParser(Parser root) => new _ParserIterable(root);
-
-class _ParserIterable extends IterableBase<Parser> {
-  final Parser root;
-
-  _ParserIterable(this.root);
-
-  @override
-  Iterator<Parser> get iterator => new _ParserIterator([root]);
-}
-
-class _ParserIterator implements Iterator<Parser> {
-  final List<Parser> todo;
-  final Set<Parser> seen;
-
-  _ParserIterator(Iterable<Parser> roots)
-      : todo = new List.from(roots),
-        seen = new Set.from(roots);
-
-  @override
-  Parser current;
-
-  @override
-  bool moveNext() {
-    if (todo.isEmpty) {
-      current = null;
-      return false;
-    }
-    current = todo.removeLast();
-    for (var parser in current.children) {
-      if (!seen.contains(parser)) {
-        todo.add(parser);
-        seen.add(parser);
-      }
-    }
-    return true;
-  }
-}