These both depend on jquery,
so this could remove even another script
from blocking rendering.

As Dan raised,
this should not enqueue this JS if this
isn't in the document.

Don't enqueue scripts if likes aren't enabled,
and move the dependencies to the footer,
as the script that depends on them,
'jetpack_likes_queuehandler',
is in the footer.
It doesn't seem necessary for these to be above
the footer.

It should ensure that the styles are present,
not that they aren't.