Derive DomObject with a proc macro

[nox]

This change is 

[highfive]

Heads up! This PR modifies the following files:

• @fitzgen: components/script/lib.rs, components/script/Cargo.toml, components/script/dom/bindings/reflector.rs
• @KiChjang: components/script/lib.rs, components/script/Cargo.toml, components/script/dom/bindings/reflector.rs

[highfive]

Warning

• These commits modify unsafe code. Please review it carefully!
• These commits modify script code, but no tests are modified. Please consider adding a test!

[SimonSapin]

Reviewed 9 of 9 files at r1.
Review status: all files reviewed at latest revision, 1 unresolved discussion.

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components/domobject_derive/lib.rs, line 41 at r1 (raw file):

            #[inline]
            fn reflector(&self) -> &::dom::bindings::reflector::Reflector {
                self.#first_field_name.reflector()

Change this to a fully qualified call? ::dom::bindings::reflector::DomObject::reflector(&self.#first_field_name). Same for init_reflector below. r=me with that.

---

Comments from Reviewable

[nox]

A trait is always imported in itself, so it's not a problem to not fully-qualify that.

@bors-servo r=SimonSapin

[bors-servo]

📌 Commit c84cea9 has been approved by SimonSapin

[bors-servo]

⌛ Testing commit c84cea9 with merge 2af79b8...

[bors-servo]

☀️ Test successful - android, arm32, arm64, linux-dev, linux-rel-css, linux-rel-wpt, mac-dev-unit, mac-rel-css, mac-rel-wpt1, mac-rel-wpt2, windows-gnu-dev, windows-msvc-dev
Approved by: SimonSapin
Pushing 2af79b8 to master...

[Ms2ger]

Change this to a fully qualified call? ::dom::bindings::reflector::DomObject::reflector(&self.#first_field_name). Same for init_reflector below. r=me with that.

I think we should still do this, to ensure that it is indeed a DomObject method we're calling.

[nox]

AFAIK it won't compile when it could be ambiguous.