Date patterns that contains four digit year does not work properly with DatePicker and DateTextField in 1.4.7.
Steps to reproduce the error:
1. Create a form with a DateTextField, a DatePicker with a four digit year pattern like yyyy-MM-dd and a submit button.
2. Run the project. Click on the DatePicker and select a date. For example 2010-03-25.
3. Submit the Form and check what's submitted to the server. Server receives the date as 0010-03-25.
A quickstart to reproduce the problem is attached.