Fix flicker when swiching resolution change

After the "Local Layout"[1] is enabled, the client can compute its
layout on its own. If we update cutout in the Display callback(server
side), it would have a timing issue that we draw the cutout(latest from
server) in the old layout(not being updated yet in client) which would
cause flicker.

We should only update cutout in client side callback like configuration
change to make sure it syncs with the current layout attributes in
client side.

For rounded corner part, we don't need to reload drawable everytime the
config is changed. Only size update is needed.

[1]:If9488ffc84dc5e2af106acfae425a854fb7407a2

Bug: 228284551
Bug: 244693677
Test: 1. Go Settings-> Display-> Screen resolution
      2. Switch between FHD <-> QHD and no flickering
Test: atest ScreenDecorationsTest RoundedCornerResDelegateTest
Change-Id: Idd45af5aa2b9419eb91994eb2071e5be616204b7