Fix color picker preview cropped in RTL (2/2)

The issue is related to how linear layout resolves layout directions. In
OnMeasure, layout direction has been resolved and therefore adding
start and end margins creates unexpected results. Add margins in xml
directly to resolve.

Flag: EXEMPT bug fix
Bug: 345608553
Test: manually verified with RTL and LTR
Change-Id: I26fc403d2bb26ff35514f217954abf72531d4700