Fixes #179 -- compile error if editing files during server mode

test/dart_codegen/expect/core/string.dart

 part of dart.core;
  abstract class String implements Comparable<String>, Pattern {external factory String.fromCharCodes(Iterable<int> charCodes, [int start = 0, int end]);
  external factory String.fromCharCode(int charCode);
  external const factory String.fromEnvironment(String name, {
   String defaultValue}
 );
  String operator [](int index);
  int codeUnitAt(int index);
  int get length;
  int get hashCode;
@@ skipping 67 matching lines @@
 RangeError.checkValidIndex(rawIndex, string, "rawIndex");
  reset(rawIndex);
  moveNext();
 }
  void reset([int rawIndex = 0]) {
 RangeError.checkValueInInterval(rawIndex, 0, string.length, "rawIndex");
  _checkSplitSurrogate(rawIndex);
  _position = _nextPosition = rawIndex;
  _currentCodePoint = null;
 }
- int get current => DEVC$RT.cast(_currentCodePoint, num, int, "ImplicitCast", """line 702, column 23 of dart:core/string.dart: """, _currentCodePoint is int, true);
+ int get current => DEVC$RT.cast(_currentCodePoint, num, int, "ImplicitCast", """line 702, column 22 of dart:core/string.dart: """, _currentCodePoint is int, true);
  int get currentSize => _nextPosition - _position;
  String get currentAsString {
 if (_position == _nextPosition) return null;
  if (_position + 1 == _nextPosition) return string[_position];
  return string.substring(_position, _nextPosition);
 }
  bool moveNext() {
 _position = _nextPosition;
  if (_position == string.length) {
 _currentCodePoint = null;
@@ skipping 27 matching lines @@
   _position = position - 1;
    _currentCodePoint = _combineSurrogatePair(prevCodeUnit, codeUnit);
    return true;
   }
 }
  _position = position;
  _currentCodePoint = codeUnit;
  return true;
 }
 }