ui/vc: drop have_text

If there are no "text" listener, the callback will simply be ignored.
The rest of text handling can be done cheaply.

This allows to remove some dependency on DisplayState from VC
implementation.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20230830093843.3531473-6-marcandre.lureau@redhat.com>
1 file changed