UX updates for notif history

- no relative time
- fix background color in dark theme
- fix text alignment in RTL

Test: manual
Fixes: 160061165
Fixes: 160388261
Fixes: 156410384
Change-Id: I7d4c5a5f81ce5b5ce43fdaa3ee99184906753a76
(cherry picked from commit 3dd023f3)