NEON-1132 Implemented a work around for this, which seems to be an issue in OpenLayers.  Whenever dom elements resize or move that trigger a position change in the map's element, the map needs to have its updateSize() method called to make the zoombox work.  Since our zoombox is predicated on a shift+drag, we're updating the size on a shift down and track whether we've seen a subsequent keyup on the shift key so we don't repeatedly resize.