macosx: refinements of minimized view behaviour

- Fix wrong playlist resize
- Minimize view state is now retained from start up to stop of video.
  Using the playlist button will result in the playlist to show up, but it
  will be always hidden when video finally stops.
- Minimize view state is exited when the user uses alt to go back to normal view.

close #9722
macosx: change alignment of dropzone-box yet again

refs #9722