BUG: set correct xlims for lines (#11471, #11310)
BUG: set correct xlims for lines (#11471, #11310)

 * Do not assume that xdata is sorted.
 * Use numpy.nanmin() and numpy.nanmax() instead.

nmartensen/pandas,nmartensen/pandas,nmartensen/pandas,nmartensen/pandas,nmartensen/pandas,nmartensen/pandas