Object.defineProperty polyfill breaks any other library dependent on that method.

```
What steps will reproduce the problem?
1. Object.defineProperty polyfill is not correct
2. It checks whether __defineGetter__ etc. is defined, which is deprecated.
3. Solution: Don't manipulate defineProperty if it's available. No other && is 
required.


```

Original issue reported on code.google.com by `cmarten...@gmail.com` on 26 Sep 2013 at 12:34
