Fix pattern for SimpleDateFormat

Fixes exception found while testing this scenario:
1. Emulator Android API 16
2. From globe button, add Afade (Latin) - SIL Cameroon QWERTY keyboard
3. From browser, install keyboard package from 
https://keyman.com/keyboard/sil_cameroon_qwerty
4.  Return to language picker, and add new keyboard
5. This triggers SimpleDateFormat()