This is a prep commit to add the status emoji feature.
We update the templates associated with the emoji
picker to add class `status_emoji` to `emoji` in the
popover. So we can later add the events when the user
selects the emoji.
We also update the functions in `emoji_picker.js` to
support opening emoji picker popover in the 'set_status_
overlay`.
We also increase the `z-index` of the `popover-flex`
class (This class is only added to popover-emoji content
if the view is mobile), so in the mobile view the emoji
popover doesn't go behind the '#set_user_status_modal'.
This fixes a bundle of issues where we were missing "" around
attributes coming from variables. In most cases, the variables were
integers or fixed constants from the Zulip codebase (E.g. the name of
an installed integration), but in at least one case it was
user-provided data that could potentially have security impact.