Handle special argument -1 to switch_ratio as intended.

Reset to the original aspect ratio that would have been used for
the very first rescaling rather than to the display size ratio.

This will now handle anamorphic videos correctly as well.


git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@36391 b3059339-0415-0410-9bf9-f77b7e298cf2
Adjust detection of original aspect ratio after r36391.


git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@36392 b3059339-0415-0410-9bf9-f77b7e298cf2