Solid angle within the mask as a function of color and magnitude.

def plotSolidAngleMMD(self):
        """
        Solid angle within the mask as a function of color and magnitude.
        """
        msg = "'%s.plotSolidAngleMMD': ADW 2018-05-05"%self.__class__.__name__
        DeprecationWarning(msg)

        import ugali.utils.plotting        

        ugali.utils.plotting.twoDimensionalHistogram('mask', 'mag_2', 'mag_1',
                                                     self.solid_angle_mmd,
                                                     self.roi.bins_mag,
                                                     self.roi.bins_mag,
                                                     lim_x = [self.roi.bins_mag[0],
                                                              self.roi.bins_mag[-1]],
                                                     lim_y = [self.roi.bins_mag[-1],
                                                              self.roi.bins_mag[0]])