core: fixed doAction when new widget is already existing and visible: when the doAction new widget was existing and visible, the factory was creating a new one, which could result in a consusing situation for the user (share widget's attachment added to an non visible widget for instance).

f95d0c31d45558c7b3e2fc39398f51eb0190bdca 0.7.0a1
4233be74572a1af8eebd502c009a10641c63ca0c 0.7.0a3
5c28cf8815319abd8c963022091cf4726764a3e6 0.7.0b1
51f73d210da908c9fb292e6bd7fda42a9d2b8453 0.7.0