Clean up before making all setting page render edge-to-edge

These classes are casting view to LinearLayout unnecessarily. Later we
might change the root view away from LinearLayout. The cast will cause
crash.

Bug: 132182711
Test: go through SUW.
Change-Id: Iea31882f8edea0c87ef8e95b4da9b6bffa8ea7d0
7 files changed