Fixing possible null dereference.

[valeriyvan]

According to coding standards in 'Creating and Returning NSError Objects' the parameter may be null

New Pull Request Checklist

• [ ] I have searched for a similar pull request in the project and found none

• [ ] I have updated this branch with the latest master to avoid conflicts (via merge from master or rebase)

• [ ] I have added the required tests to prove the fix/feature I am adding

• [ ] I have updated the documentation (if necessary)

• [ ] I have run the tests and they pass

• [ ] I have run the lint and it passes (pod lib lint)

This merge request fixes / refers to the following issues: ...

Pull Request Description

...

[lolgear]

@valeriyvan

Hi! thanks for so many PR requests! But could you reduce amount of them? Most of PRs are related to JWTDesktopSwift. It would be nice to have one PR that improves code quality. Another PRs are essential (null dereference) or aesthetic (fix spelling).

It would be nice to have groups of PRs.

[valeriyvan]

I have spent time making commits granular. One thing = one commit = separate PR. Granular PRs usually ease work making easy rejecting just one not liked thing among many changes.
Could you please accept these PRs as is? Next time I will make PRs more grouped.