Cloning this repository:

git clone git://gitorious.org/~jbarbosa/qtwebkit/jbarbosas-performance.git jbarbosas-performance
cd jbarbosas-performance

Add this repository as a remote to an existing local repository:

git remote add jbarbosas-performance git://gitorious.org/~jbarbosa/qtwebkit/jbarbosas-performance.git
git fetch jbarbosas-performance
git checkout -b my-local-tracking-branch jbarbosas-performance/master_or_other_branch