Ensure transparent hit test region is sized and positioned correctly.
This addresses some edge cases that were missed by #22156. Specifically, in some cases the transparent region was being placed in the display list in front of the scrollable content, rather than behind it, and the size of the region did not account for parent stacking context.
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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix#22073 and fix#22216.
- [x] There are tests for these changes
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Reduce unnecessary iframe size messages
This should be an improvement on pages that include iframes, since we currently run two layout jobs for every display-oriented layout request. When building the display list, we send a message to the constellation that includes the sizes of all iframes present, and the constellation sends resize messages to the script thread. This results in a mouse event on the outer page causing all frames to be re-laid out even if no changes occurred to the iframe sizes, which is ridiculous.
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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix#22394
- [x] These changes do not require tests because there is no way to test this internal detail.
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Have background, border and gradient modules
for calculation functions.
Use shorter names for functions that are qualified
by the module name like `border::radii`.
Use push_item and push_iter to add items to WebRender.
Respect CSS border-image-width.
Properly support gradients as a border-image-source.
Only emit a border item if the border-width is non-zero
for simple borders but still emit one if the item is
an image as paint worklet that are not drawn cause servo
to hang and fail tests.
Add a new test and mark 4 more as passing.
The Servo internal display list items are already pretty much
equivalent to the WebRender ones. Except that Servo items contain
base information and associated glyphs and gradient stops which are
stored implicitly in WebRender. Remove the display items for
rectangles, text, images, border, gradients and box shadow and
replace them with their WebRender counter parts.
Transforms should always create containing blocks. This bug already
existed in Servo, but was covered up by the reference frame id
replacement feature in WebRender. Now that we create reference frames
manually we need to fix it.
Now that WebRender gives us reference frame ClipIds, we can use those to
implement fixed positioning in Servo. This will allow us to remove the
feature from WebRender entirely.
