Use KCM to capitalize characters, instead of toUpperCase()

Some charaters don't get capitalized by the the keyboard based on
what is configured in the respective KCM, so we should use KCM
to see what the capitalized version of the character would look like.

Bug: 321938411
Test: manual
Change-Id: I896bb8f7526c7e2d6c516d3cc0d30c4567f65236