Wrong text baseline with usetex.

With current master, examples/pylab_examples/usetex_baseline_test.py produces the following image. And the baseline is wrong when usetex is used.

![figure_1](https://f.cloud.github.com/assets/95962/507941/3742a204-bd7a-11e2-9a90-ff06edeaa4d6.png)

It used to work fine and it still does in v1.2.x.

http://matplotlib.org/examples/pylab_examples/usetex_baseline_test.html

Any clue what changed this?