Fix serialization of timing-function
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`transition-timing-function` and `animation-timing-function` properties corrected to reflect [the spec](https://drafts.csswg.org/css-transitions/#serializing-a-timing-function). It was converting function keywords to `cubic-bezier` or `steps` functions directly. But we needed to store it to use in the serialization step.
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Allow sharing non-common style affecting attribute selectors.
Something I just noticed while re-reading that code is that we prevent sharing among siblings with different non-common attributes, even though we already have the infra to match those selectors:
```rust
if !match_same_not_common_style_affecting_attributes_rules(element,
candidate_element,
shared_context) {
miss!(NonCommonAttrRules)
}
```
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Support property aliases
Aliases now get forwarded to their "original" property name at parse time. CSSOM continues to provide access through alias getters.
We'll need to probably add `${"-webkit-foo -moz-foo" if gecko else ""}` all over the place. Might want to come up with a convenient attibute name for that (`gecko_prefix="mw"`) or something.
r? @heycam or @bholley
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Tidy assignments
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I've added a new tidy rule (no = in the beginning of line) + tests for it. Also cleaned up a few rust source files to accord with the new rule.
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Upgrade to rustc 1.16.0-nightly (6f1ae663e 2017-01-06)
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An in-memory RNG that shares its file descriptor.
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This PR implements an in-memory random number generator that only uses an OS RNG for (re)seeding. The OS RNG is shared, so there's only one file descriptor for `/dev/urandom` being used.
The PR also implements a tidy check that we don't accidentally introduce an RNG. Rather annoyingly, there are a lot of transitive dependencies on `rand`, notably hash maps in `std`.
This PR makes it possible to use uuids for identifiers such as pipeline and frame ids.
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Add support for -moz-top-layer
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r? @Manishearth
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