Select popover is positioned incorrectly the first time in Safari

[camwest]

Please walk through the following steps for reporting an issue about Orion:

Short description of your issue:

See animated gif for a demo. The first time you open a select menu either via the keyboard or the mouse it is positioned incorrectly. Subsequent opens are positioned correctly.

How do we reproduce the issue?

Please post a public URL and ideally post a reduced test case. E.g. on jsbin.com that exhibits only your issue and nothing else.

1. Visit react-playground
2. Open select menu (notice positioning)
3. Close select menu
4. Re-open select menu

What browsers are affected?

Tested in Safari, Chrome, Firefox, only noticed it in Safari

Which Orion version is affected?

Unknown, current master