I believe you have to install the app itself and allow permissions to edit your contacts. Google disallowed this feature awhile back because of numerous user complaints and data security breaches. I know some people want it, but I am glad it was removed. One of the main concerns (besides the obscene amount of access/permissions that the app and facebook connectivity want) is that it took and uploaded all contact data from your phone (not just facebook contacts) and then subsequently overwrote them or deleted them if say a friend changed what is viewable in facebook.
This was an egregious violation of privacy and trust. For example, If I removed a friend, family member, co-worker etc from facebook or they closed their account, changed what was viewable on FB, suspended it temporarily, were hacked, etc etc it completely removed that contact and all data (even it were never in facebook before and had only existed on my phone) I actually lost my grandmothers number this way.
I'm sure there are many workarounds if you honestly want that "functionality," but a safer bet would be to use a contact exporter/importer. I won't even allow facebook (the app) or a direct in-android account link to any of my devices anymore because of prior concerns.
EDIT: You can still check what contacts facebook has from your devices by going to https://www.facebook.com/invite_history.php all links and ways to find it have been hidden deep in options