issue: Controller's shouldUnregister prop is mutating defaultValues object

[TheMoonDawg]

Version Number

7.28.1

Codesandbox/Expo snack

https://codesandbox.io/s/new-rain-wgxvv1?file=/src/Form.js

Steps to reproduce

The shouldUnregister prop on Controller is mutating the defaultValues object used to instantiate the form.

1. Click Toggle Form to unmount the form.
2. Click it again to render the form.
3. Notice that firstName is no longer populated AS WELL as the defaultValues object being mutated in the console.

Note: The shouldUnregister flag on register does not produce this bug (as noted in the code sandbox).

Expected behaviour

Controller should not be mutating the object being passed into defaultValues.

What browsers are you seeing the problem on?

Firefox

Relevant log output

No response

Code of Conduct

• I agree to follow this project's Code of Conduct

[TheMoonDawg]

Thanks so much @bluebill1049 ! 🙇🏻