The label has translatable text and a help tooltip (if translated for).
The label.
object translations[id].name is the string
to use as label's text, translations[id].help is the string to use as
the label's tooltip. If id is undefined or null, translations.name
and translations.help are used.
toolkit.HTMLControlContainerElement [optional] Where to put the
label.
string [optional] Where to look in translations for the text.
string [optional] The id attribute of the HTML element
that this element refers to.