Charts - address issue with independently create cartesian series destructor method.

Propose fix for #1472.

Need to test:
- [ ] ie6
- [ ] ie7
- [ ] ie8
- [ ] ie9
- [ ] ie10
- [ ] ie11
- [ ] mac safari
- [ ] ios safari
- [ ] android 2.3.x
- [ ] android 4.1.x
- [ ] firefox
- [ ] chrome