* Add unexposed account setting for hiding poll creation
This is to match the sticker picker setting we already have, but not exposed in the user settings until we decide if we actually want it to be there.
This is primarily intended to be used in environments that disable it at the config level, though given there's multiple people in the wild who have asked for this, it seems reasonable to expose it as a hidden setting instead. Note that as of writing it's not clear if any of those requests made it as far as an issue tracker.
Typically for the usecase presented we'd add a new UIFeature flag, however this *feels* wrong for the case at hand.
* Move visibility check way higher
* Fix i18n post-merge
* Render a CollapsibleButton's children (needed by UploadButton)
* Make UploadButton ready to live inside an overflow menu
* Always show overflow menu in composer: main buttons are emoji and attach
* Re-order composer buttons as per design
* Re-word composer button captions to be simple nouns
* Don't rotate More options button when clicked
* Move the composer menu and dialogs 16px in from right
* Reduce shadow on composer More menu
* From review: remove else clause
* From review: take input out of button
* Update test snapshots
* Update snapshots
