Fixe for Issue #1751

[AnsonT]

Please read and mark the following check list before creating a pull request:

• [X] I read and followed the CONTRIBUTING.md guide.

• [X] I read and followed the New Feature Checklist guide.

  Short description of what this resolves:

This fixes issue https://github.com/akveo/react-native-ui-kitten/issues/1751 Under some rendering conditions, Argument 0 (NSNumber) of UIManager.measureInWindow must not be null error is raised.

[robpearmain]

This error is occurring regularly when I use the overflow menu from the root screen. It would be great if this could be approved and rolled out

[saadnvd1]

^ Same, could we get this merged? Thanks!