Use enum BorderWidth instead of a tuple-like struct to store the specified
value. BorderWidth is needed to be used in both longhand and shorthand
border width properties, so I put it in `specified` module.
Fixed#13869.
Run style tests with all properties included
This turns on all properties (including stylo-only ones) when the style unit tests are compiled. This lets us test the parsing of gecko-only properties.
These tests can't go in tests/stylo since this introduces dependencies on `Gecko_*` symbols. This method lets us test parsing and serialization of geckolib properties compiled in Servo mode (e.g. using Servo atoms, Servo URLs)
r? @emilio
<!-- 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/13386)
<!-- Reviewable:end -->
12902 typedefs
<!-- Please describe your changes on the following line: -->
Using type alias instead of newtype.
Removing duplicated implementation, it's already inherited.
No more type constructors and foo.0
---
<!-- 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
- [X] These changes fix#12902 (github issue number if applicable).
<!-- Either: -->
- [X] These changes do not require tests because it's refactoring.
<!-- 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/12918)
<!-- Reviewable:end -->
