Improve Launcher ←→ touch menu interaction
Needs to move the label from PanelItemRow to Panel because how clipping works in those items (and fixes some other problems too)
If launcher is locked visible:
* Touch menus show shifted to the right to not overlap
* Showing the app drawer closes the touch menus
* Showing the touch menus closes the app drawer
If launcher is not locked visible:
* Showing the launcher closes the touch menus
* Showing the touch menus closes the launcher (LP: #1667620, #1671069)
Approved by: Lukáš Tinkl, Unity8 CI Bot