Auto merge of #17150 - asajeffrey:script-paint-worklets-plumbing, r=jdm

Implemented the plumbing for paint worklets

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This PR implements the plumbing for paint worklets:

* Adding CSS values for paint worklets.
* Implementing a skeleton for the `PaintWorkletGlobalScope` webidl.
* Implementing an executor for paint worklet tasks, and passing it from script to layout.
* Building the display list items for paint worklet images.

This PR does not implement registering or calling paint worklets in JS.

Before it merges, this PR needs a reftest added for basic paint worklet functionality.

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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [ ] There are tests for these changes

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1 files changed, 4 insertions, 0 deletions

diff --git a/components/script_layout_interface/message.rs b/components/script_layout_interface/message.rs
index 038967fdd04..104de7da3d9 100644
--- a/components/script_layout_interface/message.rs
+++ b/components/script_layout_interface/message.rs
@@ -14,6 +14,7 @@ use profile_traits::mem::ReportsChan;
 use rpc::LayoutRPC;
 use script_traits::{ConstellationControlMsg, LayoutControlMsg, LayoutMsg as ConstellationMsg};
 use script_traits::{ScrollState, UntrustedNodeAddress, WindowSizeData};
+use script_traits::PaintWorkletExecutor;
 use servo_url::ServoUrl;
 use std::sync::Arc;
 use std::sync::mpsc::{Receiver, Sender};
@@ -84,6 +85,9 @@ pub enum Msg {
     /// Tells layout about a single new scrolling offset from the script. The rest will
     /// remain untouched and layout won't forward this back to script.
     UpdateScrollStateFromScript(ScrollState),
+
+    /// Tells layout that script has added some paint worklet modules.
+    SetPaintWorkletExecutor(Arc<PaintWorkletExecutor>),
 }