Fix Magnification shortcut option content overlap with top and bottom dialog container

Problem: After SuW theme applied, the scrollview viewport seems can draw outside of bounds.
Solution: Define whether a child is limited to draw inside of its bounds or not.

Test: Run initBCTestEnv_S.sh and apply different color
Bug: 187007290
Change-Id: Ie3a27616d7f30804c30e5101d2488216df516578