Regression: substract fails on compound path

[iconexperience]

Here is a simple test case that used to work, but now fails.

This bug only occurs if both of the circles exists and if the smaller circle is counter-clockwise.

var cp = new CompoundPath();
cp.addChild(new Path.Circle(100, 60, 50));
cp.addChild(new Path.Circle(100, 60, 30));
cp.addChild(new Path({segments:[
    [120, 140],
    [150, 140],
    [150, 190],
    [120, 190]], closed:true}));
cp.strokeColor = "green";

p = new Path({segments:[
    [135, 200],
    [135, 120],
    [170, 120],
    [170, 200]
], closed:true});

p.strokeColor = "red";
var r = cp.subtract(p);
r.fillColor = "rgba(255, 0, 0, .2)";

[iconexperience]

Please look at my comment in #869, this may be very easy to fix.