servo: Merge #17364 - Implement paint worklet properties (from asajeffrey:script-paint-worklets-properties); r=jdm

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This is the final PR to get basic paint worklet support. It adds support for paint worklet properties (https://drafts.css-houdini.org/css-paint-api/#paint-definition-input-properties). When a paint worklet is registered, it specifies a list of CSS properties, and is provided with their computed values when it is invoked.

This is a dependent PR:
* "Implemented paint worklets invoking worklet scripts" is #17239.
* "Implemented paint worklets rendering contexts" is #17326.

There should be tests added for this, hopefully the existing wpt houdini tests.

---
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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #16839
- [x] There are tests for these changes

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Source-Repo: https://github.com/servo/servo
Source-Revision: bc44246fc682d9f2362eaca6bba07b45c293eb42

servo/components/script/script_thread.rs

@@ -79,7 +79,7 @@ use net_traits::request::{CredentialsMode, Destination, RedirectMode, RequestIni
 use net_traits::storage_thread::StorageType;
 use profile_traits::mem::{self, OpaqueSender, Report, ReportKind, ReportsChan};
 use profile_traits::time::{self, ProfilerCategory, profile};
-use script_layout_interface::message::{self, NewLayoutThreadInfo, ReflowQueryType};
+use script_layout_interface::message::{self, Msg, NewLayoutThreadInfo, ReflowQueryType};
 use script_runtime::{CommonScriptMsg, ScriptChan, ScriptThreadEventCategory};
 use script_runtime::{ScriptPort, StackRootTLS, get_reports, new_rt_and_cx};
 use script_traits::{CompositorEvent, ConstellationControlMsg};
@@ -718,8 +718,8 @@ impl ScriptThread {
         SCRIPT_THREAD_ROOT.with(|root| {
             let script_thread = unsafe { &*root.get().unwrap() };
             script_thread.worklet_thread_pool.borrow_mut().get_or_insert_with(|| {
-                let chan = script_thread.chan.0.clone();
                 let init = WorkletGlobalScopeInit {
+                    script_sender: script_thread.chan.0.clone(),
                     resource_threads: script_thread.resource_threads.clone(),
                     mem_profiler_chan: script_thread.mem_profiler_chan.clone(),
                     time_profiler_chan: script_thread.time_profiler_chan.clone(),
@@ -728,11 +728,20 @@ impl ScriptThread {
                     scheduler_chan: script_thread.scheduler_chan.clone(),
                     image_cache: script_thread.image_cache.clone(),
                 };
-                Rc::new(WorkletThreadPool::spawn(chan, init))
+                Rc::new(WorkletThreadPool::spawn(init))
             }).clone()
         })
     }
 
+    pub fn send_to_layout(&self, pipeline_id: PipelineId, msg: Msg) {
+        let window = self.documents.borrow().find_window(pipeline_id);
+        let window = match window {
+            Some(window) => window,
+            None => return warn!("Message sent to layout after pipeline {} closed.", pipeline_id),
+        };
+        let _ = window.layout_chan().send(msg);
+    }
+
     /// Creates a new script thread.
     pub fn new(state: InitialScriptState,
                port: Receiver<MainThreadScriptMsg>,