Charts - Fix for when Bar/Column series throw errors when used independently.

Addressed issue in which independently used Bar/Column series instances had errors.

Proposed fix for: https://github.com/yui/yui3/issues/1390

Need to test:
- [ ] ie6
- [ ] ie7
- [ ] ie8
- [ ] ie9
- [ ] ie10
- [ ] ie11
- [ ] mac safari
- [ ] ios safari
- [ ] android 2.3.4
- [ ] android 4.1.1
- [ ] firefox
- [ ] chrome