fields.move causes an error when applied to two objects with different set of fields

[dekhanov]

Bug report

This issue was originally described at final-form/react-final-form-arrays#39
It looks like it's more about the final-form-arrays, then about the react-final-form-arrays

What is the current behavior?

field.move causes an error when applied to two objects with different set of fields.

Look at the demo: https://codesandbox.io/s/x94j811oj4
Open the console and click a swap button

What is the expected behavior?

To swap objects with no error

What's your environment?

See the CodeSandBox link

[seeden]

I see this error after merge 3.0.1 version

[erikras]

Published fix in v3.0.2.