servo: Merge #17505 - Remove unnecessary `recv` in the constellation (from cbrewster:less_blocking); r=asajeffrey,glennw

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Source-Repo: https://github.com/servo/servo
Source-Revision: 82f65f6eb38400affcc8e8bbc9023f345baf3942

--HG--
extra : subtree_source : https%3A//hg.mozilla.org/projects/converted-servo-linear
extra : subtree_revision : 7bc5b0604156f6622162331e8d4e05ebb01b41e6

servo/components/compositing/compositor.rs

@@ -10,7 +10,7 @@ use euclid::{Point2D, TypedPoint2D, TypedVector2D, TypedRect, ScaleFactor, Typed
 use gfx_traits::Epoch;
 use gleam::gl;
 use image::{DynamicImage, ImageFormat, RgbImage};
-use ipc_channel::ipc::{self, IpcSender, IpcSharedMemory};
+use ipc_channel::ipc::{self, IpcSharedMemory};
 use msg::constellation_msg::{Key, KeyModifiers, KeyState, CONTROL};
 use msg::constellation_msg::{PipelineId, PipelineIndex, PipelineNamespaceId, TraversalDirection};
 use net_traits::image::base::{Image, PixelFormat};
@@ -459,9 +459,9 @@ impl<Window: WindowMethods> IOCompositor<Window> {
                 self.change_page_title(pipeline_id, title);
             }
 
-            (Msg::SetFrameTree(frame_tree, response_chan),
+            (Msg::SetFrameTree(frame_tree),
              ShutdownState::NotShuttingDown) => {
-                self.set_frame_tree(&frame_tree, response_chan);
+                self.set_frame_tree(&frame_tree);
                 self.send_viewport_rects();
                 self.title_for_main_frame();
             }
@@ -673,13 +673,8 @@ impl<Window: WindowMethods> IOCompositor<Window> {
         }
     }
 
-    fn set_frame_tree(&mut self,
-                      frame_tree: &SendableFrameTree,
-                      response_chan: IpcSender<()>) {
+    fn set_frame_tree(&mut self, frame_tree: &SendableFrameTree) {
         debug!("Setting the frame tree for pipeline {}", frame_tree.pipeline.id);
-        if let Err(e) = response_chan.send(()) {
-            warn!("Sending reponse to set frame tree failed ({}).", e);
-        }
 
         self.root_pipeline = Some(frame_tree.pipeline.clone());
 

servo/components/compositing/compositor_thread.rs

@@ -91,7 +91,7 @@ pub enum Msg {
     /// Alerts the compositor that the given pipeline has changed whether it is running animations.
     ChangeRunningAnimationsState(PipelineId, AnimationState),
     /// Replaces the current frame tree, typically called during main frame navigation.
-    SetFrameTree(SendableFrameTree, IpcSender<()>),
+    SetFrameTree(SendableFrameTree),
     /// The load of a page has begun
     LoadStart,
     /// The load of a page has completed

servo/components/constellation/constellation.rs

@@ -2870,13 +2870,7 @@ impl<Message, LTF, STF> Constellation<Message, LTF, STF>
         // with low-resource scenarios.
         debug!("Sending frame tree for browsing context {}.", browsing_context_id);
         if let Some(frame_tree) = self.browsing_context_to_sendable(browsing_context_id) {
-            let (chan, port) = ipc::channel().expect("Failed to create IPC channel!");
-            self.compositor_proxy.send(ToCompositorMsg::SetFrameTree(frame_tree,
-                                                                     chan));
-            if port.recv().is_err() {
-                warn!("Compositor has discarded SetFrameTree");
-                return; // Our message has been discarded, probably shutting down.
-            }
+            self.compositor_proxy.send(ToCompositorMsg::SetFrameTree(frame_tree));
         }
     }