This change adds support for canceling CSS transitions when a property
is no longer transitionable or when an element becomes styled with
display:none. Support for canceling and replacing CSS transitions when
the end value changes is still pending. This change also takes advantage
of updating the constellation message to fix a bug where transition
events could be sent for closed pipelines.
Fixes#15079.
There is no need to set the dirty descendants flag unsafely from the layout side
for elements with pending restyles, we can do that on the DOM side when draining
the restyles from the Document.
Everytime a new LayoutContext was created, it created a new origin which
caused endless stream of image loads to occur in case of reflow. The reason
for this was that the existing image, although cached successfully, was not
used because the entry in hashmap did not match because of different(new)
origin.
This is solved by storing the origin of a window in enum ScriptReflow and
used in creating new LayoutContext in case of reflow.
This query is used to get the clientTop, clientWidth, clientHeight,
clientLeft properties of DOM objects. "NodeGeometry" doesn't really
capture what these properties do as they often are returning the width
of element border.
There are a few canvas2d-related dependencies that haven't updated, but they
only use euclid internally so that's not blocking landing the rest of the
changes.
Given the size of this patch, I think it's useful to get this landed as-is.
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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Added comment about layout thread exit workflow
Comments
Regarding clarify layout-thread exit workflow (Specifically:when will a Exit message be received )
Added comment about layout thread exit workflow
Instead of per-document. This also allows to reuse this thread-pool if needed
for other stuff, like parallel CSS parsing (#22478), and to share more code with
Gecko, which is always nice.
