Properly make stacking contexts for inlines
Instead of making a stacking context out of inline fragments parent
flow, make the inline fragment itself the stacking context. This fixes
positioning and rendering of these sort of fragments and prevents
over-layerization.
Fixes#7424.
Fixes#5812.
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Instead of making a stacking context out of inline fragments parent
flow, make the inline fragment itself the stacking context. This fixes
positioning and rendering of these sort of fragments and prevents
over-layerization.
Fixes#7424.
Fixes#5812.
There is no good reason to have the two types.
This also means that the result of LayoutTask::profiler_metadata no longer
borrows the LayoutTask, which I'll need later.
Move Stylesheet loading and ownership from the layout task into HTML elements
Stylesheets for `HTMLLinkElement`s are now loaded by the resource task, triggered by the element in question. Stylesheets are owned by the elements they're associated with, which can be `HTMLStyleElement`, `HTMLLinkElement`, and `HTMLMetaElement` (for `<meta name="viewport">).
Additionally, the quirks mode stylesheet (just as the user and user agent stylesheets a couple of commits ago), is implemented as a lazy static, loaded once per process and shared between all documents.
This all has various nice consequences:
- Stylesheet loading becomes a non-blocking operation.
- Stylesheets are removed when the element they're associated with is removed from the document.
- It'll be possible to implement the CSSOM APIs that require direct access to the stylesheets (i.e., ~ all of them).
- Various subtle correctness issues are fixed.
One piece of interesting follow-up work would be to move parsing of external stylesheets to the resource task, too. Right now, it happens in the link element once loading is complete, so blocks the script task. Moving it to the resource task would probably be fairly straight-forward as it doesn't require access to any external state.
Depends on #7979 because without that loading stylesheets asynchronously breaks lots of content.
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Stylesheets for `HTMLLinkElement`s are now loaded by the resource task, triggered by the element in question. Stylesheets are owned by the elements they're associated with, which can be `HTMLStyleElement`, `HTMLLinkElement`, and `HTMLMetaElement` (for `<meta name="viewport">).
Additionally, the quirks mode stylesheet (just as the user and user agent stylesheets a couple of commits ago), is implemented as a lazy static, loaded once per process and shared between all documents.
This all has various nice consequences:
- Stylesheet loading becomes a non-blocking operation.
- Stylesheets are removed when the element they're associated with is removed from the document.
- It'll be possible to implement the CSSOM APIs that require direct access to the stylesheets (i.e., ~ all of them).
- Various subtle correctness issues are fixed.
One piece of interesting follow-up work would be to move parsing of external stylesheets to the resource task, too. Right now, it happens in the link element once loading is complete, so blocks the script task. Moving it to the resource task would probably be fairly straight-forward as it doesn't require access to any external state.
Remove DisplayListBuildingResult
Always produce a DisplayList when processing nodes for display list
construction. StackingContexts are now added to the positioned content
section of DisplayLists. This makes the code a bit simpler and opens up
the possibility of producing a StackingContext in another section of
the DisplayList. This doesn't change behavior, but is a cleanup
prerequisite for proper inline stacking context support.
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