Auto merge of #20083 - yurket:19840_enable_css_pain_api_and_remove_forked_duplicates, r=jdm

enable css paint api and remove forked duplicates

1) Move paintWorklet from "Window" to "CSS" according to new specification;
2) Enable WPT css-paint-api tests from upstream and remove forked duplicates from mozilla folder

- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #19840
- [X] These changes do not require tests because the change was made in tests it-selves

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components/script/dom/css.rs

@@ -6,8 +6,10 @@ use cssparser::{Parser, ParserInput, serialize_identifier};
 use dom::bindings::codegen::Bindings::WindowBinding::WindowBinding::WindowMethods;
 use dom::bindings::error::Fallible;
 use dom::bindings::reflector::Reflector;
+use dom::bindings::root::DomRoot;
 use dom::bindings::str::DOMString;
 use dom::window::Window;
+use dom::worklet::Worklet;
 use dom_struct::dom_struct;
 use style::context::QuirksMode;
 use style::parser::ParserContext;
@@ -63,4 +65,9 @@ impl CSS {
             false
         }
     }
+
+    /// <https://drafts.css-houdini.org/css-paint-api-1/#paint-worklet>
+    pub fn PaintWorklet(win: &Window) -> DomRoot<Worklet> {
+        win.paint_worklet()
+    }
 }

components/script/dom/webidls/CSS.webidl

@@ -17,3 +17,8 @@ partial interface CSS {
   static boolean supports(DOMString property, DOMString value);
   static boolean supports(DOMString conditionText);
 };
+
+// https://drafts.css-houdini.org/css-paint-api-1/#paint-worklet
+partial interface CSS {
+    [SameObject, Pref="dom.worklet.enabled"] static readonly attribute Worklet paintWorklet;
+};

components/script/dom/webidls/Window.webidl

@@ -196,8 +196,3 @@ partial interface Window {
    readonly attribute TestRunner testRunner;
    //readonly attribute EventSender eventSender;
 };
-
-// https://drafts.css-houdini.org/css-paint-api-1/#paint-worklet
-partial interface Window {
-    [SameObject, Pref="dom.worklet.enabled"] readonly attribute Worklet paintWorklet;
-};

components/script/dom/window.rs

@@ -1022,17 +1022,17 @@ impl WindowMethods for Window {
         fetch::Fetch(&self.upcast(), input, init)
     }
 
-    // https://drafts.css-houdini.org/css-paint-api-1/#paint-worklet
-    fn PaintWorklet(&self) -> DomRoot<Worklet> {
-        self.paint_worklet.or_init(|| self.new_paint_worklet())
-    }
-
     fn TestRunner(&self) -> DomRoot<TestRunner> {
         self.test_runner.or_init(|| TestRunner::new(self.upcast()))
     }
 }
 
 impl Window {
+    // https://drafts.css-houdini.org/css-paint-api-1/#paint-worklet
+    pub fn paint_worklet(&self) -> DomRoot<Worklet> {
+        self.paint_worklet.or_init(|| self.new_paint_worklet())
+    }
+
     pub fn task_canceller(&self) -> TaskCanceller {
         TaskCanceller {
             cancelled: Some(self.ignore_further_async_events.borrow().clone()),