Theme secondary default app picker screen for car settings

One major difference is that car settings doesn't use radio buttons.
Instead it uses "Selected" string in the summary field to denote the
default app.

For (system apps)s, the text will appear as "Selected - (System app)"

Bug: 130348508
Test: manual
Change-Id: Iac2e45add29cd923b77c685064aa0d5d65e39965