WebIDL HTMLConstructor support
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spec: https://html.spec.whatwg.org/multipage/#htmlconstructor
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- [X] These changes fix#17194 (github issue number if applicable).
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Fix setting img src before window.onload causing panic
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Setting an image source asynchronously (e.g. using `setTimeout` or in the callback of an `XMLHttpRequest`) before `window.onload` fired would cause a panic due to a preexisting load blocker not being terminated before assigning a new one.
This PR fixes that and adds a test for it.
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- [x] These changes fix#17319.
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windows: fix line height handling
hi there!
on windows, this change properly scales a font's line height by its size.
previously, line height was not scaled to the font's size at all, which meant line heights become worse and worse the further you scaled away from the font's design size (in either direction, larger or smaller).
this change makes the `line_gap` ratio and size scale with the font size. i've hand checked that the new computed `line_gap` matches the effective heights in chrome and firefox when `line-height = normal` for a bunch of system fonts. (servo's rendering quality on windows is a different story, though).
i believe this also solves #16476.
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Avoid panic when reloading a page with mouse event handlers
This PR fixes issue #16057, by nullifying `topmost_mouse_over_target` inside of the `handle_exit_pipeline_msg` method, in case owner document is the same as the pipeline document that is being destroyed.
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
Testing was done manually, by running `./mach run (-r|-d) "http://localhost:8000/minimal.html" `, where `minimal.html` contains `<div onmouseover="location.reload()" onmouseout="this.clientLeft">hi there</div>`.
r?@jdm
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Now we have AnimatableLonghand (to do with animatability) and
TransitionProperty (to do with transitionability), we should move
nscssproperty_id_is_animatable to be part of the former group.
Currently properties that are discretely animated cannot be
transitioned. Now that TransitionProperty should only be used for
transitions, we can redefine it to treat non-transitionable properties
as unsupported. This should allow us to simplify the code and make it
more self-documenting (e.g. making TransitionProperty actually relate to
transitions).
