It looks like the development of PackageKit happens outside of the master branch in git, the last version on the master branch is 0.7.4. It can be seen on the web interface also: http://cgit.freedesktop.org/packagekit/
We moved to github: https://github.com/hughsie/PackageKit
Oh, this is not mentioned on the homepage, which still points to an old repository on gitorious.org: http://www.freedesktop.org/software/PackageKit/pk-download.html
commit 9470acd32ec80b57b8c7ba0f689d25b77afe8b67 Author: Richard Hughes <richard@hughsie.com> Date: Tue Sep 30 11:02:23 2014 +0100 Update the webpages to reflect reality Resolves: https://bugs.freedesktop.org/show_bug.cgi?id=84488
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