Code review comment for lp:~nick-dedekind/unity-api/shell_chrome

> "Shell chrome" is a mir concept, but my understanding is that it refers to
> whether "non application" parts of the shell (indicators in our use case) are
> visible.

So, it is a hint from the server to the client, telling the client about a shell visual state, allowing client to decide surface state? Or is it a hint from the client to the server to recommend server to hide its chrome? What if server doesn't support or allow different chrome modes?

Also, are we're implying that "low chrome" is zero chrome?

I can find no documentation for the exact purpose of this thing in Mir. Frankly I'm not a fan of it.

> For how this relates to the bug; we have changed touch apps to use low chrome
> mode when wanting "full screen" in phone/tablet form factor, and Window.state
> = FullScreen when wanting it in desktop mode.

I understand this is now Mir api, but I won't be the first person to find this confusing. If this is indeed a hint from server->client, then (aside from "low chrome" being a vague concept) at least it means the client can decide the suitable surface state. If it a client->server hint, I'm less clear on what happens.