Incorrect reporting of duplicate IDs in Shadow DOM

[samdutton]

Report from @tomayac :

I think it's incorrect about duplicate IDs that are in Shadow DOM. The toggle appears four times on the page and the extension thinks the IDs are duplicate, but they are unique to each Shadow DOM.

https://googlechromelabs.github.io/dark-mode-toggle/demo/index.html

[samdutton]

@socsieng I remember some discussion of Shadow DOM stuff.

As Tom says, each <dark-mode-toggle> has the same IDs.