bug#27357: 26.0.50; Emacs starts fullscreen in Ubuntu 17.04

[martin rudalics]

> I just noticed something amusing: If I put the mouse over the mode line
> things that pop up tooltips, they're all displayed approximately 2x from
> the position they're supposed to:
>
> https://youtu.be/oWjmL-8leVo
>
> This is with the current git Emacs, with -Q on Ubuntu 17.04 (with a
> HiDPI display).

See bug#18429, bug#20619, bug#21348, bug#21469 ...

martin