Use PositioningUtils in Dropdown

[henningmu]

Instead of calculating the placement ourselves it should be possible to reuse (the already tested) logic from PositioningUtils and / or the Tooltip component.

[rimildeyjsr]

@henningmu - Can I work on this?

[gnapse]

I'd suggest we wait to see where we land with the popover approach. This issue has been around for a while now, and a lot has happened since that may change what we do about it.

Specifically, we just migrated the tooltip to use reakit underneath (#276 to be merged and released soon), and we're in the process of doing the same for the menu (PR in the works, not yet pushed). Both of these components are key users of the popover positioning logic and by using reakit they're no longer using our internal popover solution. I'm not entirely sure right now what will this mean in the mid and long term for our popover. So maybe we can wait before investing time into this.

[rimildeyjsr]

@gnapse - Thanks for the update! 😃