How do I access the handles of stem plot lines and markers separately in R2015a??

Prior to R2015, the stem function returned a handle which could be used to get the handles of the two children that corresponded to the line and marker components of the stem plot.

In R2015a, stem returns the handle of a matlab.graphics.chart.primitive.Stem object whose 'Children' is an empty graphics placeholder. How do I access handles for the line and marker separately? In my applications -- which all worked seamlessly before I DOWNGRADED to R2015a -- I need the ButtonDownFcn to be triggered only when the markers are clicked, not the lines.