Implement Element.client{Top,Left,Width,Height}
This isn't done, but contains a working implementation of at least `clientTop`. Feedback would be much appreciated: it's probably far from ideal.
Implementing `clientLeft` is straight-forward, I think, but `clientWidth` and `clientHeight` require accessing the `border_box` - and I don't know how that works, yet.
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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.
The idea here is to land this before making images and canvas IPC-safe,
because this will shake out bugs relating to the shared memory. There
are currently test timeouts that are preventing multiprocess images and
canvas from landing, and I believe those are due to the inefficiency of
sending large amounts of data in the unoptimized builds we test with. By
moving to shared memory, this should drastically reduce the number of
copies and `serde` serialization.
Under the hood, this uses Mach OOL messages on Mac and temporary
memory-mapped files on Linux.
By doing this on either side of the call to the relevant tasks' start()
method, we don't need to store the mem::ProfilerChan or the reporter
name in the task itself.
This commit introduces the `serde` dependency, which we will use to
serialize messages going between processes in multiprocess Servo.
This also adds a new debugging flag, `-Z print-display-list-json`,
allowing the output of display list serialization to be visualized.
This will be useful for our experiments with alternate rasterizers.
process parts.
This will make it easier to adapt to IPC.
The trickiest part here was to make script tasks spawn new layout tasks
directly instead of having the pipeline do it for them. The latter
approach will not work in multiprocess mode, because layout and script
must run in the same address space and the pipeline cannot inject tasks
into another process.
Reduce the scope of the allowed unsafe code in context.rs.
Since I made unsafe code opt-in in layout, the unsafe code in this module has
been reduced to a single unsafe impl, so there is no reason to allow it in
the entire module.
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Since I made unsafe code opt-in in layout, the unsafe code in this module has
been reduced to a single unsafe impl, so there is no reason to allow it in
the entire module.
