Auto merge of #11410 - Ms2ger:script-listener-thread, r=nox

Remove the script listener thread.

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.

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3 files changed, 30 insertions, 43 deletions

diff --git a/components/script/dom/document.rs b/components/script/dom/document.rs
index 42708265325..89755564bb6 100644
--- a/components/script/dom/document.rs
+++ b/components/script/dom/document.rs
@@ -106,8 +106,8 @@ use parse::{ParserRoot, ParserRef, MutNullableParserField};
 use script_thread::{MainThreadScriptMsg, Runnable};
 use script_traits::UntrustedNodeAddress;
 use script_traits::{AnimationState, MouseButton, MouseEventType, MozBrowserEvent};
-use script_traits::{ScriptMsg as ConstellationMsg, ScriptToCompositorMsg};
-use script_traits::{TouchpadPressurePhase, TouchEventType, TouchId};
+use script_traits::{ScriptMsg as ConstellationMsg, TouchpadPressurePhase};
+use script_traits::{TouchEventType, TouchId};
 use std::ascii::AsciiExt;
 use std::borrow::ToOwned;
 use std::boxed::FnBox;
@@ -636,10 +636,10 @@ impl Document {
     /// Sends this document's title to the compositor.
     pub fn send_title_to_compositor(&self) {
         let window = self.window();
-        let compositor = window.compositor();
-        compositor.send(ScriptToCompositorMsg::SetTitle(window.pipeline(),
-                                                        Some(String::from(self.Title()))))
-                  .unwrap();
+        window.constellation_chan()
+              .send(ConstellationMsg::SetTitle(window.pipeline(),
+                                               Some(String::from(self.Title()))))
+              .unwrap();
     }
 
     pub fn dirty_all_nodes(&self) {
@@ -1049,7 +1049,7 @@ impl Document {
                               key: Key,
                               state: KeyState,
                               modifiers: KeyModifiers,
-                              compositor: &IpcSender<ScriptToCompositorMsg>) {
+                              constellation: &IpcSender<ConstellationMsg>) {
         let focused = self.get_focused_element();
         let body = self.GetBody();
 
@@ -1124,7 +1124,7 @@ impl Document {
         }
 
         if !prevented {
-            compositor.send(ScriptToCompositorMsg::SendKeyEvent(key, state, modifiers)).unwrap();
+            constellation.send(ConstellationMsg::SendKeyEvent(key, state, modifiers)).unwrap();
         }
 
         // This behavior is unspecced
diff --git a/components/script/dom/window.rs b/components/script/dom/window.rs
index e5af0ebbf26..63a0ca2a36e 100644
--- a/components/script/dom/window.rs
+++ b/components/script/dom/window.rs
@@ -62,7 +62,7 @@ use script_runtime::{ScriptChan, ScriptPort};
 use script_thread::SendableMainThreadScriptChan;
 use script_thread::{MainThreadScriptChan, MainThreadScriptMsg, RunnableWrapper};
 use script_traits::{ConstellationControlMsg, UntrustedNodeAddress};
-use script_traits::{DocumentState, MsDuration, ScriptToCompositorMsg, TimerEvent, TimerEventId};
+use script_traits::{DocumentState, MsDuration, TimerEvent, TimerEventId};
 use script_traits::{ScriptMsg as ConstellationMsg, TimerEventRequest, TimerSource};
 use std::ascii::AsciiExt;
 use std::borrow::ToOwned;
@@ -153,8 +153,6 @@ pub struct Window {
     image_cache_chan: ImageCacheChan,
     #[ignore_heap_size_of = "channels are hard"]
     custom_message_chan: IpcSender<CustomResponseSender>,
-    #[ignore_heap_size_of = "TODO(#6911) newtypes containing unmeasurable types are hard"]
-    compositor: IpcSender<ScriptToCompositorMsg>,
     browsing_context: MutNullableHeap<JS<BrowsingContext>>,
     performance: MutNullableHeap<JS<Performance>>,
     navigation_start: u64,
@@ -340,10 +338,6 @@ impl Window {
         &self.image_cache_thread
     }
 
-    pub fn compositor(&self) -> &IpcSender<ScriptToCompositorMsg> {
-        &self.compositor
-    }
-
     pub fn browsing_context(&self) -> Root<BrowsingContext> {
         self.browsing_context.get().unwrap()
     }
@@ -775,7 +769,7 @@ impl WindowMethods for Window {
         // Step 1
         //TODO determine if this operation is allowed
         let size = Size2D::new(x.to_u32().unwrap_or(1), y.to_u32().unwrap_or(1));
-        self.compositor.send(ScriptToCompositorMsg::ResizeTo(size)).unwrap()
+        self.constellation_chan.send(ConstellationMsg::ResizeTo(size)).unwrap()
     }
 
     // https://drafts.csswg.org/cssom-view/#dom-window-resizeby
@@ -790,7 +784,7 @@ impl WindowMethods for Window {
         // Step 1
         //TODO determine if this operation is allowed
         let point = Point2D::new(x, y);
-        self.compositor.send(ScriptToCompositorMsg::MoveTo(point)).unwrap()
+        self.constellation_chan.send(ConstellationMsg::MoveTo(point)).unwrap()
     }
 
     // https://drafts.csswg.org/cssom-view/#dom-window-moveby
@@ -976,13 +970,13 @@ impl Window {
         let size = self.current_viewport.get().size;
         self.current_viewport.set(Rect::new(Point2D::new(Au::from_f32_px(x), Au::from_f32_px(y)), size));
 
-        self.compositor.send(ScriptToCompositorMsg::ScrollFragmentPoint(
-                                                         self.pipeline(), layer_id, point, smooth)).unwrap()
+        let message = ConstellationMsg::ScrollFragmentPoint(self.pipeline(), layer_id, point, smooth);
+        self.constellation_chan.send(message).unwrap();
     }
 
     pub fn client_window(&self) -> (Size2D<u32>, Point2D<i32>) {
         let (send, recv) = ipc::channel::<(Size2D<u32>, Point2D<i32>)>().unwrap();
-        self.compositor.send(ScriptToCompositorMsg::GetClientWindow(send)).unwrap();
+        self.constellation_chan.send(ConstellationMsg::GetClientWindow(send)).unwrap();
         recv.recv().unwrap_or((Size2D::zero(), Point2D::zero()))
     }
 
@@ -1180,7 +1174,7 @@ impl Window {
         let pipeline_id = self.id;
 
         let (send, recv) = ipc::channel::<Point2D<f32>>().unwrap();
-        self.compositor.send(ScriptToCompositorMsg::GetScrollOffset(pipeline_id, layer_id, send)).unwrap();
+        self.constellation_chan.send(ConstellationMsg::GetScrollOffset(pipeline_id, layer_id, send)).unwrap();
         recv.recv().unwrap_or(Point2D::zero())
     }
 
@@ -1450,7 +1444,6 @@ impl Window {
                file_task_source: FileReadingTaskSource,
                image_cache_chan: ImageCacheChan,
                custom_message_chan: IpcSender<CustomResponseSender>,
-               compositor: IpcSender<ScriptToCompositorMsg>,
                image_cache_thread: ImageCacheThread,
                resource_threads: ResourceThreads,
                bluetooth_thread: IpcSender<BluetoothMethodMsg>,
@@ -1490,7 +1483,6 @@ impl Window {
             custom_message_chan: custom_message_chan,
             console: Default::default(),
             crypto: Default::default(),
-            compositor: compositor,
             navigator: Default::default(),
             image_cache_thread: image_cache_thread,
             mem_profiler_chan: mem_profiler_chan,
diff --git a/components/script/script_thread.rs b/components/script/script_thread.rs
index e07e0ad64f7..ffb4125845b 100644
--- a/components/script/script_thread.rs
+++ b/components/script/script_thread.rs
@@ -81,7 +81,7 @@ use script_traits::CompositorEvent::{TouchEvent, TouchpadPressureEvent};
 use script_traits::{CompositorEvent, ConstellationControlMsg, EventResult};
 use script_traits::{InitialScriptState, MouseButton, MouseEventType, MozBrowserEvent, NewLayoutInfo};
 use script_traits::{LayoutMsg, ScriptMsg as ConstellationMsg};
-use script_traits::{ScriptThreadFactory, ScriptToCompositorMsg, TimerEvent, TimerEventRequest, TimerSource};
+use script_traits::{ScriptThreadFactory, TimerEvent, TimerEventRequest, TimerSource};
 use script_traits::{TouchEventType, TouchId};
 use std::borrow::ToOwned;
 use std::cell::{Cell, RefCell};
@@ -350,9 +350,6 @@ pub struct ScriptThread {
     /// For communicating layout messages to the constellation
     layout_to_constellation_chan: IpcSender<LayoutMsg>,
 
-    /// A handle to the compositor for communicating ready state messages.
-    compositor: IpcSender<ScriptToCompositorMsg>,
-
     /// The port on which we receive messages from the image cache
     image_cache_port: Receiver<ImageCacheResult>,
 
@@ -465,7 +462,6 @@ 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.send(ScriptToCompositorMsg::Exited);
                 let _ = script_thread.content_process_shutdown_chan.send(());
             }, reporter_name, script_chan, CommonScriptMsg::CollectReports);
 
@@ -577,7 +573,6 @@ impl ScriptThread {
             control_port: control_port,
             constellation_chan: state.constellation_chan,
             layout_to_constellation_chan: state.layout_to_constellation_chan,
-            compositor: state.compositor,
             time_profiler_chan: state.time_profiler_chan,
             mem_profiler_chan: state.mem_profiler_chan,
             panic_chan: state.panic_chan,
@@ -1301,8 +1296,8 @@ 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.send(ScriptToCompositorMsg::Exit).unwrap();
+        // constellation. In the future it'll need to be smarter.
+        self.constellation_chan.send(ConstellationMsg::Exit).unwrap();
     }
 
     /// We have received notification that the response associated with a load has completed.
@@ -1459,7 +1454,6 @@ impl ScriptThread {
                                  FileReadingTaskSource(file_sender.clone()),
                                  self.image_cache_channel.clone(),
                                  self.custom_message_chan.clone(),
-                                 self.compositor.clone(),
                                  self.image_cache_thread.clone(),
                                  self.resource_threads.clone(),
                                  self.bluetooth_thread.clone(),
@@ -1682,8 +1676,11 @@ impl ScriptThread {
         let point = Point2D::new(rect.origin.x.to_nearest_px() as f32,
                                  rect.origin.y.to_nearest_px() as f32);
 
-        self.compositor.send(ScriptToCompositorMsg::ScrollFragmentPoint(
-                                                 pipeline_id, LayerId::null(), point, false)).unwrap();
+        let message = ConstellationMsg::ScrollFragmentPoint(pipeline_id,
+                                                            LayerId::null(),
+                                                            point,
+                                                            false);
+        self.constellation_chan.send(message).unwrap();
     }
 
     /// Reflows non-incrementally, rebuilding the entire layout tree in the process.
@@ -1768,16 +1765,14 @@ impl ScriptThread {
                 let handled = self.handle_touch_event(pipeline_id, event_type, identifier, point);
                 match event_type {
                     TouchEventType::Down => {
-                        if handled {
+                        let result = if handled {
                             // TODO: Wait to see if preventDefault is called on the first touchmove event.
-                            self.compositor
-                                .send(ScriptToCompositorMsg::TouchEventProcessed(
-                                        EventResult::DefaultAllowed)).unwrap();
+                            EventResult::DefaultAllowed
                         } else {
-                            self.compositor
-                                .send(ScriptToCompositorMsg::TouchEventProcessed(
-                                        EventResult::DefaultPrevented)).unwrap();
-                        }
+                            EventResult::DefaultPrevented
+                        };
+                        let message = ConstellationMsg::TouchEventProcessed(result);
+                        self.constellation_chan.send(message).unwrap();
                     }
                     _ => {
                         // TODO: Calling preventDefault on a touchup event should prevent clicks.
@@ -1794,7 +1789,7 @@ 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, &self.compositor);
+                document.dispatch_key_event(key, state, modifiers, &self.constellation_chan);
             }
         }
     }