scroll, SetScrollTop, SetScrollLeft in `element.rs`
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Currently dom-element-scroll have not finished yet. (Step 10)
This PR finish the step 10 of `scroll`, `SetScrollTop`, `SetScrollLeft`
[Step 10 description](https://drafts.csswg.org/cssom-view/#dom-element-scrolltop):
> If the element does not have any associated CSS layout box, the element has no associated scrolling box, or the element has no overflow, terminate these steps.
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- [X] These changes fix#19114 (github issue number if applicable).
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- [X] There are tests for these changes
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- Change domparsing spec link from domparsing.spec.whatwg.org to w3c.github.io/DOM-Parsing
- Remove from tidy since it's already covered by w3c.github.io
- Update test manifest
* scrollLeft/scrollTop returned values of parent or even document root
Only the scroll of the node itself is returned. Otherwise 0.0.
* Scrolling via script had set viewport.
This resulted in other nodes appearing scrolled.
Now scroll_offsets are updated with correct node id.
These bugs caused other odd behavior like both body and
document.documentElement being scrolled or the view for scrolled
elements jumping.
Remove the assert_readonly test and add one to verify that assigning to
CSSStyleRule.style correctly forwards to CSSStyleRule.style.cssText.
We currently test for whether CSSStyleRule.style is read-only by
trying to assign to it; however, the spec has it as actually:
interface CSSStyleRule : CSSRule {
...
[SameObject, PutForwards=cssText] readonly attribute CSSStyleDeclaration style;
};
See: https://drafts.csswg.org/cssom/
The `PutForwards=cssText` means that assigning to CSSStyleRule.style
should actually assign to style.cssText.
