Reduce screen layout in task override configuration from its parent config

This prevented scheduling unexpected screen layout size
changes to client when entering PIP.

Bug: 111811414
Test: atest ActivityManagerPinnedStackTests
Test: go/wm-smoke
Change-Id: I6ff55bedad29df2ae3d00cdd18a748c052fae750
Merged-In: I6ff55bedad29df2ae3d00cdd18a748c052fae750
(cherry picked from commit 48bfeeb568b2afee9a8dcc67c2774c0883f6824c)
1 file changed