Fixed an issue where the qs panel wasn't properly placed

The QS panel should only be placed below the notifications
if it has notifications above the shelf. This ensures that
all animations including icons are appearing in the right
place.

Test: runtest -x packages/SystemUI/tests/src/com/android/systemui/statusbar/ExpandableNotificationRowTest.java
Test: runtest -x packages/SystemUI/tests/src/com/android/systemui/statusbar/notification/AboveShelfObserverTest.java
Fixes: 35305470
Change-Id: I97fb0c76ed69b7638ce83a7c06856d87bf6bf65f