This is the same shape text editing indicator that's available in Writer
and Impress already.

Change-Id: I5f7fbf2efdc92a10b169a3f1b27e24426f3dfb3d
Reviewed-on: https://gerrit.libreoffice.org/27507Reviewed-by: Miklos Vajna <vmiklos@collabora.co.uk>
Tested-by: Jenkins <ci@libreoffice.org>