feat(messaging): support for frameId

[Mehdi-Hp]

Adding support for optional frameId in Browser.tabs.sendMessage

[aklinker1]

Thanks for the PR and updating the tests.

One small change, I prefer to avoid runtime type-checks if typescript already reports as fine. The error the browser throws in those cases is good enough.

[aklinker1]

Looks like there are some type errors in src/extension.test-d.ts causing checks to fail

[Mehdi-Hp]

Looks like there are some type errors in src/extension.test-d.ts causing checks to fail

Fixed.
Updated the docs too, but I think that needs your edit.