Fix #1477: Popups showing incorrectly in multitasking on iOS13.

[iccub]

Summary of Changes

This pull request fixes issue #1477

Submitter Checklist:

• Unit Tests are updated to cover new or changed functionality
• User-facing strings use NSLocalizableString()

Test Plan:

Check the popups on iOS 13 for both multitasking mode and not

Screenshots:

Reviewer Checklist:

• Issues include necessary QA labels:
  • QA/(Yes|No)
  • release-notes/(include|exclude)
  • bug / enhancement
• Necessary security reviews have taken place.
• Adequate unit test coverage exists to prevent regressions.
• Adequate test plan exists for QA to validate (if applicable).
• Issue is assigned to a milestone (should happen at merge time).

[kylehickinson]

What happens if we change the modal presentation style from overFullScreen to overCurrentContext in the popover? Might that fix this bug?

[iccub]

this works @kylehickinson
Are there any drawbacks by switching to overCurrentContext ?

[kylehickinson]

@iccub Only thing that would change is if we were presenting the popover from a child controller. It would then take the frame of that child, but since we don't do that anywhere there's no difference from overFullScreen in this context