Make Attr::prefix an Atom

[tamird]

Rebase of https://github.com/Ms2ger/servo/commits/ICE-attr-prefix-atom

Some of the changes weren't necessary since the internals had been refactored some in the interim. In any case, I was unable to reproduce the ICE reported in rust-lang/rust#18957.

@Ms2ger

[highfive]

Thanks for the pull request, and welcome! The Servo team is excited to review your changes, and you should hear from @Manishearth (or someone else) soon.

[jdm]

That.. is dedication. Thanks @tamird!

[bors-servo]

☔ The latest upstream changes (presumably #5852) made this pull request unmergeable. Please resolve the merge conflicts.

[tamird]

@jdm @Ms2ger any interest in this?

[jdm]

Yes, I'll make sure it's reviewed by the end of tomorrow.

[jdm]

Reviewed files:

• components/script/dom/attr.rs @ r2
• components/script/dom/bindings/utils.rs @ r2
• components/script/dom/create.rs @ r3
• components/script/dom/document.rs @ r3
• components/script/dom/element.rs @ r3
• components/script/dom/node.rs @ r3

---

^{components/script/dom/node.rs, line 1737 [r3] (raw file):}
Atom::from_slice(&p)

---

---

Comments from the review on Reviewable.io

[jdm]

-S-awaiting-review +S-needs-code-changes

---

Comments from the review on Reviewable.io

[tamird]

^{components/script/dom/node.rs, line 1737 [r3] (raw file):}
Done.

---

---

Comments from the review on Reviewable.io

[jdm]

@bors-servo: r+

-S-awaiting-review +S-awaiting-merge

---

Reviewed files:

• components/script/dom/attr.rs @ r4
• components/script/dom/create.rs @ r4
• components/script/dom/document.rs @ r4
• components/script/dom/element.rs @ r4
• components/script/dom/node.rs @ r4

---

Comments from the review on Reviewable.io

[bors-servo]

📌 Commit 9435565 has been approved by jdm

[bors-servo]

⌛ Testing commit 9435565 with merge b0a7d1b...

[bors-servo]

☀️ Test successful - android, gonk, linux1, linux2, mac1, mac2