More grid serialization and parsing fixes
These are the bugs I discovered while I was re-enabling the disabled grid mochitests. Now all grid mochitests are passing! Additionally I converted `Vec<CustomIdent>`'s into `Box<[CustomIdent]>`. We are storing so many line names in vectors. These should help a bit.
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We have checks for these in the shorthand parsing side actually.
But if we need to serialize a group of longhand sub-properties for the shorthand,
we should be able to fail for invalid grammar gracefully. This patch adds these checks.
It was storing both TrackSize and TrackRepeat before and TrackRepeat have to be
converted into sequence of TrackSize during serialization. Instead of doing this
in serialization process(which is hard and hacky), we converted to do this in
parsing process. We were doing this conversion in the ComputedValue conversion.
So we only had to move this process to parsing.
Handling of invalid values in svg paint server
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This is a PR for https://bugzilla.mozilla.org/show_bug.cgi?id=1374161
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There are tests for these changes, a test case will be landed in reftests in https://bugzilla.mozilla.org/show_bug.cgi?id=1374161.
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Add support for subgrids and fix some other grid properties
This covers the `subgrid <line-name-lists>?` for `grid-template` (for gecko, and hence, stylo).
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It was printing `repeat(n, <line-names>)` for number TrackRepeat.
But it should just print n times <line-names> instead.
MozReview-Commit-ID: FEmL8O2osVb
Convert -webkit-linear-gradient coordinate system for Stylo
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This patch will fix the -webkit-linear-gradient direction issue in Stylo. I decided to NOT change the behavior of Servo, because according to the webcompat spec the webkit prefixed version should just be an alias of non-prefixed version. But we might want to remove support for old syntax like "-webkit-linear-gradient(top, ...)" (without "to"), because they are not in the spec anymore.
The Gecko layout system use different coordinate systems for prefixed and non-prefixed version, so I did a conversion, but for Servo I keep the modern version only.
Since I believe we should not support old syntax in Servo, so I'm not going to put the test in Servo. I'll submit my test cases to the Gecko wpt test instead.
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- [x] These changes fix [Bug 1372821](https://bugzilla.mozilla.org/show_bug.cgi?id=1372821)
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We simply implement ToCss for Option<T>, printing nothing if the value is None,
and we then use SequenceWriter to skip writing of separators around empty parts.
A future patch series has some values that should be separated by spaces. This
allows us to re-use the code for serialization, but the types do get a little
clunky. The separator is now indicated with an associated type.
