ClutterText replaces ClutterLabel, so it should expose the same
kind of API - ideally with the minimal amount of changes, so that
the porting is trivial.
The TidyText actor is meant as a replacement for both ClutterLabel
and ClutterText.
Any text-displaying and editing actor should derive from ClutterText
and implement the various visual cues to differentiate the editable
from the non-editable state. Those visual cues usually belong to
a high-level toolkit, especially if themeing is involved.