Without this, the charts tend to crash on double-click.

This kind of reverts commit 86ea687d.

Change-Id: I462e4beec71008a0abe29ec0bb570c8a35c82a7f
Reviewed-on: https://gerrit.libreoffice.org/50408Reviewed-by: Marco Cecchetti <mrcekets@gmail.com>
Tested-by: Marco Cecchetti <mrcekets@gmail.com>
Reviewed-on: https://gerrit.libreoffice.org/50481Tested-by: Jenkins <ci@libreoffice.org>