Looks good to me.

Ok, so how do I do this properly? I haven't tried doing a merge into v1.0.x and then into master.

Not sure. I think Darren should know (and there are plans to add these instructions to the developer docs eventually)

First make sure your v1.0.x branch is fresh:

git checkout v1.0.x
git pull --ff-only upstream v1.0.x

(This assumes an "upstream" remote pointing to git://github.com/matplotlib/matplotlib.git.) Then merge your pull request and run the test suite (I don't know if this should be mandatory):

git merge bugfix/legend_windowcall
python setup.py install # or however you compile things to run the tests
./tests.py # all new test runner script!

If everything is fine, push:

git push git@github.com:matplotlib/matplotlib.git v1.0.x

Next do the same with master, this time merging v1.0.x:

git checkout master
git pull --ff-only upstream master
git merge v1.0.x
python setup.py install
./tests.py
git push git@github.com:matplotlib/matplotlib.git master

I'll post these instructions on the developer list so people can comment on them.