Auto merge of #11338 - Ms2ger:compositor-refcell, r=nox

Take ScriptThread::compositor out of its RefCell.

Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data:
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy --faster` does not report any errors
- [ ] These changes fix #__ (github issue number if applicable).

Either:
- [ ] There are tests for these changes OR
- [x] These changes do not require tests because refactoring

Pull requests that do not address these steps are welcome, but they will require additional verification as part of the review process.

There's no reason for it; IpcSender::send takes &self.

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components/script/script_thread.rs

@@ -352,7 +352,7 @@ pub struct ScriptThread {
     layout_to_constellation_chan: IpcSender<LayoutMsg>,
 
     /// A handle to the compositor for communicating ready state messages.
-    compositor: DOMRefCell<IpcSender<ScriptToCompositorMsg>>,
+    compositor: IpcSender<ScriptToCompositorMsg>,
 
     /// The port on which we receive messages from the image cache
     image_cache_port: Receiver<ImageCacheResult>,
@@ -472,7 +472,7 @@ impl ScriptThreadFactory for ScriptThread {
             let reporter_name = format!("script-reporter-{}", id);
             mem_profiler_chan.run_with_memory_reporting(|| {
                 script_thread.start();
-                let _ = script_thread.compositor.borrow_mut().send(ScriptToCompositorMsg::Exited);
+                let _ = script_thread.compositor.send(ScriptToCompositorMsg::Exited);
                 let _ = script_thread.content_process_shutdown_chan.send(());
             }, reporter_name, script_chan, CommonScriptMsg::CollectReports);
 
@@ -582,7 +582,7 @@ impl ScriptThread {
             control_port: control_port,
             constellation_chan: state.constellation_chan,
             layout_to_constellation_chan: state.layout_to_constellation_chan,
-            compositor: DOMRefCell::new(state.compositor),
+            compositor: state.compositor,
             time_profiler_chan: state.time_profiler_chan,
             mem_profiler_chan: state.mem_profiler_chan,
             panic_chan: state.panic_chan,
@@ -1308,7 +1308,7 @@ impl ScriptThread {
         // TODO(tkuehn): currently there is only one window,
         // so this can afford to be naive and just shut down the
         // compositor. In the future it'll need to be smarter.
-        self.compositor.borrow_mut().send(ScriptToCompositorMsg::Exit).unwrap();
+        self.compositor.send(ScriptToCompositorMsg::Exit).unwrap();
     }
 
     /// We have received notification that the response associated with a load has completed.
@@ -1465,7 +1465,7 @@ impl ScriptThread {
                                  FileReadingTaskSource(file_sender.clone()),
                                  self.image_cache_channel.clone(),
                                  self.custom_message_chan.clone(),
-                                 self.compositor.borrow_mut().clone(),
+                                 self.compositor.clone(),
                                  self.image_cache_thread.clone(),
                                  self.resource_threads.clone(),
                                  self.bluetooth_thread.clone(),
@@ -1688,7 +1688,7 @@ impl ScriptThread {
         let point = Point2D::new(rect.origin.x.to_nearest_px() as f32,
                                  rect.origin.y.to_nearest_px() as f32);
 
-        self.compositor.borrow_mut().send(ScriptToCompositorMsg::ScrollFragmentPoint(
+        self.compositor.send(ScriptToCompositorMsg::ScrollFragmentPoint(
                                                  pipeline_id, LayerId::null(), point, false)).unwrap();
     }
 
@@ -1776,11 +1776,11 @@ impl ScriptThread {
                     TouchEventType::Down => {
                         if handled {
                             // TODO: Wait to see if preventDefault is called on the first touchmove event.
-                            self.compositor.borrow_mut()
+                            self.compositor
                                 .send(ScriptToCompositorMsg::TouchEventProcessed(
                                         EventResult::DefaultAllowed)).unwrap();
                         } else {
-                            self.compositor.borrow_mut()
+                            self.compositor
                                 .send(ScriptToCompositorMsg::TouchEventProcessed(
                                         EventResult::DefaultPrevented)).unwrap();
                         }
@@ -1800,8 +1800,7 @@ impl ScriptThread {
             KeyEvent(key, state, modifiers) => {
                 let context = get_browsing_context(&self.root_browsing_context(), pipeline_id);
                 let document = context.active_document();
-                document.dispatch_key_event(
-                    key, state, modifiers, &mut self.compositor.borrow_mut());
+                document.dispatch_key_event(key, state, modifiers, &self.compositor);
             }
         }
     }