UINavigationBar overlays top table view cell when isInverted is set to false

[gim-]

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• I've searched for any related issues and avoided creating a duplicate issue.

Description

Navigation bar hides the very top cell when isInverted flag is set to false.

Reproducible in:

• This is reproducible in the sample project.
  SlackTextViewController version: master branch (commit: d5e01fc)
  iOS version(s): iOS 11
  Device(s): any

Steps to reproduce:

1. Open Swift Example project
2. Change self.isInverted = true to self.isInverted = false
3. Launch the project and scroll to top

Expected result:

Top table view cell should be below navigation bar

Actual result:

Top table view cell is behind navigation bar

Attachments:

https://www.dropbox.com/s/z3z9y3qyvtxrfaj/slacklib.mov?dl=0

[gim-]

This issue is not present in 4c74cba so I assume it has something to do with this change: d5e01fc

I used commit lock in my Podfile as a workaround for now:

pod 'SlackTextViewController', :git => 'https://github.com/slackhq/SlackTextViewController', :commit => '4c74cbab29408dda9af33633f86dcc983a3b5363'