Issue 8719: Add basic support for :active selector
<!-- Please describe your changes on the following line: -->
Added toggling of active state for element and parents on mousedown/mouseup. Active state is removed when mouseout. (hover)
- As with my other PR i'm struggling a bit with the automated testing. I've added a manual test case and found quirks-mode/active-and-hover-manual.html which - aside from also being a manual test, is functional in Firefox but does not render correctly in Servo.
- Not implemented: In Firefox, behaviour differs with a <!DOCTYPE HTML> and an anchor does not lose it's activation on mouseout; whereas a button does.
---
<!-- 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#8719 (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. -->
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csstext
- [x] These changes fix#4431.
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy --faster` reports one error for the `css_properties_accessors!` macro not having a spec link
```
$ git log -1 --format=oneline
91fb9bf1d3 fixup! implement cssText
$ ./mach build -d
Compiling style v0.0.1 (file:///Users/greg/servo/components/style)
Compiling gfx v0.0.1 (file:///Users/greg/servo/components/gfx)
Compiling script v0.0.1 (file:///Users/greg/servo/components/script)
Compiling layout_traits v0.0.1 (file:///Users/greg/servo/components/layout_traits)
Compiling compositing v0.0.1 (file:///Users/greg/servo/components/compositing)
Compiling glutin_app v0.0.1 (file:///Users/greg/servo/ports/glutin)
Compiling constellation v0.0.1 (file:///Users/greg/servo/components/constellation)
Compiling layout v0.0.1 (file:///Users/greg/servo/components/layout)
Compiling servo v0.0.1 (file:///Users/greg/servo/components/servo)
Build completed in 0:05:11.475584
$ ./mach test-tidy --faster
Checking files for tidiness...
./components/script/dom/cssstyledeclaration.rs:386: method declared in webidl is missing a comment with a specification link
Progress: 100% (12/12)
```
- [x] There are tests for these changes. More CSSOM tests pass, but others fail that probably shouldn't:
* `./mach test-css tests/wpt/css-tests/cssom-1_dev/html/index-002.htm` and a bunch of the other tests in `/css-tests/cssom-1_dev/html/ crash when run individually
* `./mach test-css tests/wpt/css-tests/cssom-1_dev/html/cssom-cssText-serialize.htm` fails to strip a trailing semicolon (`left: 10px` vs `left: 10px;`)
* `./mach test-css tests/wpt/css-tests/cssom-1_dev/html/index-001.htm` shared shorthand values aren't coalesced (`margin: 20px` vs. `margin: 20px 20px 20px 20px`)
* `./mach test-css tests/wpt/css-tests/cssom-1_dev/html/cssstyledeclaration-csstext.htm` also crashes and fails for `color: red;` vs. `color: RED;`, preserving declaration insertion order, whitespace in the value, and setting an unknown style property.
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Support -moz-binding in geckolib
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 --faster` does not report any errors
- [ ] These changes fix #__ (github issue number if applicable).
Either:
- [ ] There are tests for these changes OR
- [x] These changes do not require tests because changes target stylo
Pull requests that do not address these steps are welcome, but they will require additional verification as part of the review process.
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---
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Add new compositor message to get scroll_offset;
Add new layout query for computed value of overflow-x/y;
Implement layer_id method for ThreadSafeLayoutNode;
Add new layout query for layer_id;
Implement script interface for getting scrollTop and scrollLeft, as well as relavant helper functions.
