Introduce VirtualMethods::children_changed()
This virtual method mimics the behaviour of mutation observers and make it more viable than the older child_inserted(), which didn't cover removed nodes and was called as many times as there were inserted nodes.
A few other shortcomings where remove_child() was called directly instead of Node::remove() were also fixed while at it.
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To actually make the multiprocess communication work, we'll need to
reroute the task creation to the pipeline or the compositor. But this
works as a first step.
Fix a few issues
- Use SmallVec<[T; N]>
- Make find_iframe a free function
- Make ProgressEvent use enums for bubbles and cancelable
- Change README, as `rust-snapshot-hash` is just a text file
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an IPC channel instead.
Because this used a boxed trait object to invoke messages across a
process boundary, and boxed trait objects are not supported across IPC,
we spawn a helper thread inside the compositor to perform the marshaling
for us.
The util component specified fnv and smallvec as dependencies and publicly
reexported both of them. Several other components utilized these reexports,
presumably because fnv and smallvec used to live in the tree so reexporting
made the transition easier.
These indirect dependencies through the util component are unnecessary.
This commit removes the fnv & smallvec crate reexports in the util component.
It exchange, it adds fnv & smallvec as dependencies to non-util components
wherever needed. Finally, it removes the fnv dependency from util as it is not
utilized anywhere in the util component.
* Simpler image cache API for clients to use.
* Significantly fewer threads.
* One thread for image cache task (multiplexes commands, decoder threads and async resource requests).
* 4 threads for decoder worker tasks.
* Removed ReflowEvent hacks in script and layout tasks.
* Image elements pass a Trusted<T> to image cache, which is used to dirty nodes via script task. Previous use of Untrusted addresses was unsafe.
* Image requests such as background-image on layout / paint threads trigger repaint only rather than full reflow.
* Add reflow batching for when multiple images load quickly.
* Reduces the number of paints loading wikipedia from ~95 to ~35.
* Reasonably simple to add proper prefetch support in a follow up PR.
* Async loaded images always construct Image fragments now, instead of generic.
* Image fragments support the image not being present.
* Simpler implementation of synchronous image loading for reftests.
* Removed image holder.
* image.onload support.
* image NaturalWidth and NaturalHeight support.
* Updated WPT expectations.
