refactor(polyfills): do not raise a Assignment call unless needed.

[barelyhuman]

I understand the need for the polyfill, but for various security reasons a few production projects freeze the ability to modify the constructors so this basically triggers an assignment even when it's not needed and the freeze cause a failure.

Let me know if there's other considerations that you'd like to take for this

[BikashMcKinsey]

Fixes #244