DatePicker and DateTimePicker i18n and locale fix without interceptor

Problem to solve

After the i18n workaround for the DateTimePicker in the issue #356 (closed), there is a need to solve the same problem without creating an interceptor and forcing the component to be instantiated by the backend.

Further details

This fix (without instantiator interceptor) is required to use a vaadin-date-picker or a vaadin-date-time-picker in a grid with working locale support.

What does success look like, and how can we measure that?

• DatePicker and DateTimePicker without a parse interceptor
• A vaadin-date-picker or a vaadin-date-time-picker with a working locale in a grid cell.