Fix JS errors in the docs page when searching for some specific terms.

Search for "ru" here: http://static.rust-lang.org/doc/master/std/index.html and you'll get the following error in Firebug:

![screen shot 2013-10-30 at 11 42 56 pm](https://f.cloud.github.com/assets/217126/1439737/110e9b3a-418f-11e3-9da4-b7099e3892d7.png)