Auto merge of #14992 - servo:rustup, r=jdm

Upgrade to rustc 1.16.0-nightly (2782e8f8f 2017-01-12)

<!-- Please describe your changes on the following line: -->

---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data: -->
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [ ] These changes fix #__ (github issue number if applicable).

<!-- Either: -->
- [ ] There are tests for these changes OR
- [ ] These changes do not require tests because _____

<!-- Pull requests that do not address these steps are welcome, but they will require additional verification as part of the review process. -->

<!-- Reviewable:start -->
---
This change is [<img src="https://reviewable.io/review_button.svg" height="34" align="absmiddle" alt="Reviewable"/>](https://reviewable.io/reviews/servo/servo/14992)
<!-- Reviewable:end -->

components/script/dom/xmlhttprequest.rs

@@ -40,7 +40,8 @@ use encoding::all::UTF_8;
 use encoding::label::encoding_from_whatwg_label;
 use encoding::types::{DecoderTrap, EncoderTrap, Encoding, EncodingRef};
 use euclid::length::Length;
-use html5ever::serialize::{self, SerializeOpts};
+use html5ever::serialize;
+use html5ever::serialize::SerializeOpts;
 use hyper::header::{ContentLength, ContentType};
 use hyper::header::Headers;
 use hyper::method::Method;