Fix monkey bug when focus change before layout

Bug 64359848

Monkey found a divide-by-zero error caused by the width not set
when focus was changed before layout. This CL just ensures that
there is no divide by zero by selecting the first row/column.

Test: manually launched Date Picker and it didn't crash
Change-Id: Id6dd12cd20b052af71ab980c8a694020ea679e7c