'update solid, lines, etc. Unlike update_bruteforce, it does
not clear the axes.  This is meant to be called when the image
or contour plot to which this colorbar belongs is changed.'

def update_normal(self, mappable):

    self.draw_all()
    if isinstance(self.mappable, contour.ContourSet):
        CS = self.mappable
        if (not CS.filled):
            self.add_lines(CS)
    self.stale = True
