Created by: FranDias
min-height: 1px prevents a column from collapsing when there is no content inside of it (empty). This PR makes this rule applied specifically to the case of the bug that it's fixing.
Currently min-height creates undesirable behavior when animating an element's height to or from 0.
Example of annoying behavior: http://codepen.io/FranDias/pen/YWqayO (granted this is on float grid but the behavior is the same on flex grid)