Not sure if we need to keep that one, honestly I feel like it doesn't bring much value to fix it. I tested in 15.10 and the behaviour is different now: the limit is not related to a media rule in CSS, but to the width of the logo + the width of the icon, so we still have the 50px height by default, now the sum of the width of logo + navpanel is 534px so at a resolution of 534 we get a height of 57px (not sure why 7 more):

and apparently there's another computation when we continue lowering the resolution below the margins (which are of 15px) so the limit is then at 504: