Remove convert to smilies option

[chriscct7]

Given smilies are pretty much deprecated, and the (default on) option to turn :-) into smily is barely used by anyone, we should consider removing it (strongly related #5161). We have a filter for turning that off if users really want to use this. This along with #5161 would remove an entire section of barely used options from the admin, simplifying the settings and following core philosophy of decisions not options

Does anyone have an objection to this?

[pento]

See 5161#comment:16.

(Smilies will definitely be going away, but I'm waiting for opinions on balance tags before them both.)

[pento]

In 32454:

On the Writing Options screen, hide the Balance Tags and Convert Smilies options on new installs.

Fixes #5161.
Fixes #32298.

[celloexpressions]

Why only on new installs? Do we expect significant opposition from existing installs? It seems like these would typically be set once, then left, so removing the option on an existing install shouldn't be much of an issue either.

[pento]

Historically, there've been two ways of removing options:

• [23588], where we only remove it for new installs.
• [21539], where it's removed when the option setting is the default value.

I went with removing it on new installs only for a couple of reasons:

• There's no extra functionality that depends on it being removed.
• I'm more inclined to think that people will play with formatting settings more freely, and having them magically disappear seems like a weird (and potentially off-putting) UX.

[netweb]

r32454 should be reverted, bbPress and BuddyPress both use convert_smilies() and we're far from the only two plugins, see ​https://github.com/search?q=user%3Awp-plugins+convert_smilies&type=Code

Per the current releases of bbPress and BuddyPress I'd expect to be able to install WordPress 4.3 and the respective bbPress or BuddyPress versions and be able to enable this option to Convert emoticons like :-) and :-P to graphics on display and have this smiliey post content continued to be rendered graphically.

The change in r32454 removes this capability for new installs with existing plugins, I agree that this is a good decision that should be made but not right now, plugins should be given sufficient time to implement this change before forcing their hand.

[pento]

In 32455:

When saving Writing Options, check that the UI is enabled for use_smilies and use_balanceTags before trying to update them.

Fixes #5161.
Fixes #32298.