gtkplacesview: Right click popover fix crash and align menu with mouse
There is a bug that is similar to !4625 (merged) (that is for the sidebar) that crashes when right clicking different items in places (especially after unmounting / mounting)
Also, when you right click a row in places, the menu is always in the center, regardless of where you click. I fixed that in this MR
Edited by Corey Berla