Fix several bugs related to scrolling
* 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.
Also try scrolling this [example page](https://pyfisch.org/stuff/scrolltest.html) in servo with and without this change.
<!-- Please describe your changes on the following line: -->
---
<!-- 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#17342 (github issue number if applicable).
<!-- Either: -->
- [x] There are tests for these changes (partially)
<!-- Also, please make sure that "Allow edits from maintainers" checkbox is checked, so that we can help you if you get stuck somewhere along the way.-->
<!-- 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/17385)
<!-- Reviewable:end -->
This fixes another rAF bug, that is being exposed by the previous
two commits. Previously, the fake timer callback would only be
set if we were being called from a non-rAF event handler.
Now, if we're in fake / spurious mode, unconditionally set the one
shot timer.
Otherwise, notify the compositor that animations are present if
we're not currently in a rAF callback.
* 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.
This commit also removes the old restyle_hints module and splits it into
multiple modules under components/style/invalidation/element/.
The basic approach is to walk down the tree using compound selectors as needed,
in order to do as little selector-matching as possible.
Bug: 1368240
MozReview-Commit-ID: 2YO8fKFygZI
remove unused style::restyle_hints::RestyleReplacements
<!-- Please describe your changes on the following line: -->
remove unused style::restyle_hints::RestyleReplacements from line 134
---
<!-- 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#16978 (github issue number if applicable).
<!-- Either: -->
- [X] These changes do not require tests because removes only unused "use"
<!-- Also, please make sure that "Allow edits from maintainers" checkbox is checked, so that we can help you if you get stuck somewhere along the way.-->
<!-- 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/16979)
<!-- Reviewable:end -->
Renamed constellation::Frame to constellation::BrowsingContext
<!-- Please describe your changes on the following line: -->
Now that script has `WindowProxy` rather than `BrowsingContext` objects, we can rename `Frame` in the constellation to `BrowsingContext`. In particular, this means that `FrameId`s are now `BrowsingContextid`s, which better captures their purpose (and they are used in a lot of places, not just the constellation).
---
<!-- 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 do not require tests because renaming
<!-- Also, please make sure that "Allow edits from maintainers" checkbox is checked, so that we can help you if you get stuck somewhere along the way.-->
<!-- 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/16876)
<!-- Reviewable:end -->
Scroll roots are no longer nested containers holding items, so instead
we need to track the offsets of each, carefully handling fixed position
items and stacking contexts that create new reference frames.
Additionally, we remove the complexity of the pre-computed page scroll
offset, instead opting to send script scrolls to the layout task in
order to more quickly have a ScrollState there that matches the
script's idea of the scroll world.
Fixes#16405.
Eliminate ScrollRootId
Just use WebRender's ClipId directly. This will allow us to create and
use ReferenceFrames in the future, if we need to do that. It will also
make it easier to have Servo responsible for creating the root
scrolling area, which will allow removing some old hacks in the future.
<!-- Please describe your changes on the following line: -->
---
<!-- 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
- [ ] These changes fix #__ (github issue number if applicable).
<!-- Either: -->
- [ ] There are tests for these changes OR
- [x] These changes do not require tests because they should not change behavior.
<!-- Also, please make sure that "Allow edits from maintainers" checkbox is checked, so that we can help you if you get stuck somewhere along the way.-->
<!-- 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/16531)
<!-- Reviewable:end -->
Just use WebRender's ClipId directly. This will allow us to create and
use ReferenceFrames in the future, if we need to do that. It will also
make it easier to have Servo responsible for creating the root
scrolling area, which will allow removing some old hacks in the future.
Fix namespaces of elements created in XML documents
Correctly implement following step of [Dom Document Spec](https://dom.spec.whatwg.org/#dom-document-createelement):
> Let namespace be the HTML namespace, if the context object is an HTML document or context object’s content type is "application/xhtml+xml", and null otherwise.
Note, this will make following test in `tests/wpt/web-platform-tests/dom/nodes/Document-constructor.html` to fail, so related .ini file added to mark it as such:
```
test(function() {
var doc = new Document();
var a = doc.createElement("a");
// In UTF-8: 0xC3 0xA4
a.href = "http://example.org/?\u00E4";
assert_equals(a.href, "http://example.org/?%C3%A4");
}, "new Document(): URL parsing")
```
I'm not very familiar with specs, but from quick look at it, I'm doubtfull that it is valid in the first place. This is an "application/xml" document, so I don't see why it should encode a.href. Firefox also fails that.
---
<!-- 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#14095 (github issue number if applicable).
<!-- Either: -->
- [ ] There are tests for these changes OR
- [X] These changes do not require tests because because there are already tests which were being ignored
<!-- Also, please make sure that "Allow edits from maintainers" checkbox is checked, so that we can help you if you get stuck somewhere along the way.-->
<!-- 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/16472)
<!-- Reviewable:end -->
Access browsing context safely
Current browsing context accessor in `Document` unwraps the browsing context `Option` which prevents document to handle correctly the case when there is no browsing context.
This is the reason servo panics with `session-history.max-length=1` (https://github.com/servo/servo/issues/15877).
As it is my first contribution, I added a `safe` method to retrieve the browsing context rather than change the existing method, but I am happy to change if you think this is the right approach. I did not as well replace all existing method call to the `safe` method, to focus on fixing the issue.
If someone can give me a bit of guidance for the test, I will try to contribute one.
---
<!-- 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
- [ ] `./mach test-tidy` does not report any errors
- [X] These changes fix#15877.
- [ ] There are tests for these changes
<!-- 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/15906)
<!-- Reviewable:end -->
Current browsing context accessor in Document unwrap the browsing context option which prevents document to handle correctly the case when there is no browsing context.
Improve behaviour of image elements that perform multiple requests
This addresses cases where image elements end up making multiple requests, as well as makes the element respond to additional relevant mutations that trigger updating the image data.
---
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix#15709 (github issue number if applicable).
- [X] There are tests for these changes
<!-- 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/15771)
<!-- Reviewable:end -->
This better reflects the text of the specification - rather than
queuing a task to dispatch the load evnet as soon as the document
loader is unblocked, we want to "spin the event loop until there
is nothing that delays the load event in the Document." Spinning
the event loop is a concept that requires running tasks
completely, hence we check the condition before returning to the
start of the event loop.
After this patch, when the page calls `requestAnimationFrame()` too many
times in the row without actually mutating the DOM, further calls to
`rAF` will actually perform the moral equivalent of `setTimeout(16)`.
This saves a lot of CPU time compared to actually waiting for the
vertical blanking interval, because waiting for that requires us to draw
the page.
Reduces CPU usage drastically on nytimes.com, which has a perpetual
`requestAnimationFrame()` loop that checks whether ads are in view.
