DisplayCutout: make dock divider cutout aware

Fixes an issue where the insets given to SystemUI's dock divider
did not include the display cutout insets, which would lead to the
minimized view being laid out wrong.

Bug: 75277581
Test: Enter landscape, enter splitscreen, press home. Verify that there is no extra space between home and the divider.
Change-Id: I85107f147381aaceb01dfcad329662d54d72bbf7