Split chan and receiver_port into script and compositor flavors
Partial #8356. Currently this doesn't build because of a lint denying me to user unsafe code, which unfortunately the select! macro falls under. Not sure what to do there.
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Simplify multi-touch state machine code
This is a minor refactoring of the touch tracking in compositor, to simplify the code and prepare for more gesture handling (like pinch to zoom). r? @glennw
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When a layer containing an iframe changes, we also need to resize the
root layer of the subpage. This ensures that content from the child
layer tree is masked to the new size.
Fixes#8301.
This is enabled by default on Android, because Glutin currently sends mouse
events instead of touch events on Android. It's also useful for testing on
non-touch platforms.
Integrate iframes into the display list
Instead of always promoting iframes to StackingContexts, integrate them
into the display list. This prevents stacking bugs when
non-stacking-context elements should be drawn on top of iframes.
To accomplish this, we add another step to ordering layer creation,
where LayeredItems in the DisplayList are added to layers described by
the LayerInfo structures collected at the end of the DisplayList.
Unlayered items that follow these layered items are added to
synthesized layers.
Another result of this change is that iframe layers can be positioned
directly at the location of the iframe fragment, eliminating the need
for the SubpageLayerInfo struct entirely.
Iframes are the first type of content treated this way, but this change
opens up the possibility to properly order canvas and all other layered
content that does not create a stacking context.
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Instead of always promoting iframes to StackingContexts, integrate them
into the display list. This prevents stacking bugs when
non-stacking-context elements should be drawn on top of iframes.
To accomplish this, we add another step to ordering layer creation,
where LayeredItems in the DisplayList are added to layers described by
the LayerInfo structures collected at the end of the DisplayList.
Unlayered items that follow these layered items are added to
synthesized layers.
Another result of this change is that iframe layers can be positioned
directly at the location of the iframe fragment, eliminating the need
for the SubpageLayerInfo struct entirely.
Iframes are the first type of content treated this way, but this change
opens up the possibility to properly order canvas and all other layered
content that does not create a stacking context.
Fixes#7566.
Fixes#7796.
Fixes#7867 (and probably several other iframe bugs).
When collecting layers for children of a pipeline, pass through the current
subpage pipeline recursively. This prevents descendany layers (such as scroll
layers) from being collected and re-created on the subsequent paint.
Unify all compositor shutdown code paths into two methods, one which
starts the shutdown and the other that finishes it. This simplifies the
way the compositor shuts down and prevents "leaking" pixmaps when
exiting in uncommon ways.
Remove constellation round trip for subpage mapping in compositor.
This makes use of the new functionality that allows iframes to generate their own pipeline IDs in order to remove any knowledge of subpage ids from the compositor.
(This is the first of several commits removing subpage from parts of servo).
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