Revert "Remove unneeded show() in WikiEditor toolbar"

because apparently we do have empty tools boxes. Alternative
implementation in I4652ade66c6de864ee3e74b3817ed9b93967ce3d

This reverts commit dd46fc383b7b427f0824249deb078fd64a0d578d.

Change-Id: I358c34d63261989d49b0a4156cbc05b544727d5c