Comment # 2 on bug 1184948 from Dominique Leuenberger

From an IRC session with a user seeing the same, a quick debug trace pointed to

  gnome-icon-themes

owning the distributor-logo that is shown here.
g-i-t is quite outdated and obsolete, but we still have a few packages relying
on it (some other icon themes declaring an inheritance, some other packages,
most likely wrongly depending on a specific icon theme)