Pinking shears

git-svn-id: https://buddypress.svn.wordpress.org/trunk@8298 cdf35c40-ae34-48e0-9cc9-0c9da1808c22
Don't register the Friends widget on non-root blogs

This widget only works in the context of displayed users, which do not exist
outside of root blogs.

Fixes #5512

Props williamsba1

git-svn-id: https://buddypress.svn.wordpress.org/trunk@8299 cdf35c40-ae34-48e0-9cc9-0c9da1808c22