Options, Meta APIs: Toggle pre_option filters in update_option().

[costdev]

In update_option(), pre_option_{$option} filters are currently removed before getting the "raw" old value, then restored afterwards.

This change performs the same removal/restoration with pre_option filters as well.

Trac ticket: https://core.trac.wordpress.org/ticket/22192

[spacedmonkey]

@felixarntz @costdev This was by design #5313 (comment)

[felixarntz]

@costdev Per what @spacedmonkey said, I don't think we should remove the generic pre_option (or pre_site_option) filters. The idea is that those could be applied for general changes, such as never hitting the DB for options or something like that. Unhooking those could be severe for special setups like that. Unhooking a specific pre filter though should be okay, given that those would be used only on specific options, thus it would be reasonable to expect the DB isn't bypassed entirely.

[costdev]

@felixarntz @spacedmonkey Yep no worries. I didn't realise that this was already discussed.