Keep the points in front!

I find it hard to believe I didn't catch this earlier...

Test Plan:
1. Load graphing_inequalities.html and graphing_inequalities_2.html in local mode.
2. Drag a point.
3. See https://s3.amazonaws.com/uploads.hipchat.com/6574/49847/XZzptRZSBkqtTAz/upload.png instead of https://s3.amazonaws.com/uploads.hipchat.com/6574/49847/jsNjObFKhW6nAHd/upload.png

Auditors: jack