This reduces the boilerplate necessary for adding new
serializable/transferable interfaces to the structured cloning code. We
always need to root the deserialized objects when performing a read
operation, but we don't actually need the concrete object types in the
majority of cases. By storing a list of rooted JS object values, we can
push generic reflector objects into it, and extract the types we need
(MessagePort) at the very end.
Testing: Existing WPT structured cloning tests will provide coverage.
Signed-off-by: Josh Matthews <josh@joshmatthews.net>
Rather than creating unique types for each pipeline-namespaced index
type (eg. MessagePortId, DomExceptionId, etc.), we can create a generic
common type that uses a marker to prevent type confusion. This change
allows us to reduce the boilerplate code required when implementing
serializable/transferable interfaces, since the structured clone
implementation can rely on the common type.
Testing: Existing WPT tests for serialization and transferring provide
coverage.
---------
Signed-off-by: Josh Matthews <josh@joshmatthews.net>
This is the last big change necessary to create the
`constellation_traits` crate. This moves the data structure for messages
that originate from the `ScriptThread` and are sent to the
`Contellation` to `constellation_traits`, effectively splitting
`script_traits` in half. Before, `script_traits` was responsible for
exposing the API of both the `ScriptThread` and the `Constellation` to
the rest of Servo.
- Data structures that are used by `ScriptToConstellationMsg` are moved
to `constellation_traits`. The dependency graph looks a bit like this:
`script_layout_interface` depends on `script_traits` depends on
`constellation_traits` depends on `embedder_traits`.
- Data structures that are used in the embedding layer
(`UntrustedNodeAddress`, `CompositorHitTestResult`, `TouchEventResult`
and `AnimationState`) are moved to embedder_traits, to avoid a
dependency cycle between `webrender_traits` and
`constellation_traits`.
- Types dealing with MessagePorts and serialization are moved to
`constellation_traits::message_port`.
Testing: This is covered by existing tests as it just moves types
around.
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
http://www.robohornet.org gives a score of 101.36 on master,
and 102.68 with this PR. The latter is slightly better,
but probably within noise level.
So it looks like this PR does not affect DOM performance.
This is expected since `Box::new` is defined as:
```rust
impl<T> Box<T> {
#[inline(always)]
pub fn new(x: T) -> Box<T> {
box x
}
}
```
With inlining, it should compile to the same as box syntax.
In a later PR, DomRoot<T> will become a type alias of Root<Dom<T>>,
where Root<T> will be able to handle all the things that need to be
rooted that have a stable traceable address that doesn't move for the
whole lifetime of the root. Stay tuned.
Passes some but not all WPT tests. One failure is caused by an issue in codegen for the `DOMPointInit` dictionary, the others by outdated tests: Gecko implements an old version of the spec that overloaded the `DOMPoint` constructor to optionally take an object as the first argument, and made `DOMPointReadOnly` non-constructible.
