For admin list pages which contain a search box, when showing results,

there's an additional element that shows the count, with content like

"5 results (10 total)". This pushes down the list box somewhat.
The drawer element that slides out when some of the checkboxes are

selected had some manual spacing applied with the stylesheet that

aligned it with the list box, but with that extra element present, was

overlapping badly. This showed a little extra box shadow when the drawer

was hidden, but then overlapped in an ugly way when shown.
This change adds an extra step to the change-list resize handler to

reposition the drawer to align nicely no matter where the form ends up

on the page.

Looked at a change-list page with search results and saw that the drawer

lined up nicely.