Fixed an issue where the shelf was not rounded during the expansion

The positioning of the shelf was actually incorrect previously
which would lead to the rounded corners not being rounded
with a cutout. We didn't factor in the minExpandHeight when
when calculating the stack translation.

Change-Id: I50a1e8b36256426deef8816fe7e6d0c2d53842fd
Fixes: 110343077
Test: expand and collapse the notification panel while having a notch