title: flutter RTL syntax error with "package:intl/intl.dart"
body: <p>Hi i recently try to use a date Picker for flutter and i didn't find any Doc or tutorial for it so i open flutter gallery project and try to copy code .
  as following the code i import "package:intl/intl.dart" library . 
  after that in main.dart build function:</p>
  
  <pre><code>  Widget build(BuildContext context) {
  return new MaterialApp(
      title: 'Welcome to Flutter',
      theme: new ThemeData.light(),
      home: new InitiateAppPage(),
      builder: (BuildContext context, Widget child) {
        return new Directionality(
          textDirection: TextDirection.rtl,
          child: child,
        );
      },
      );   }
  </code></pre>
  
  <p>Element 'TextDirection' from SDK library 'ui.dart' is implicitly hidden by 'intl.dart'.
  any solution for this problem?</p>