Auto merge of #10150 - emilio:canvas-cleanup, r=jdm

Canvas cleanup

This PR cleans up the layerization infrastructure for canvas, which was unused, and removes unused dependencies.

It also takes in account my recent username change to update angle's dependency (offscreen_gl_context requires extra work due to webrender depending on it).

r? @jdm

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components/layout/Cargo.toml

@@ -12,9 +12,6 @@ path = "lib.rs"
 git = "https://github.com/servo/rust-azure"
 features = ["plugins"]
 
-[dependencies.canvas]
-path = "../canvas"
-
 [dependencies.canvas_traits]
 path = "../canvas_traits"
 

components/layout/context.rs

@@ -8,7 +8,6 @@
 #![allow(unsafe_code)]
 
 use app_units::Au;
-use canvas_traits::CanvasMsg;
 use euclid::Rect;
 use fnv::FnvHasher;
 use gfx::display_list::WebRenderImageInfo;
@@ -16,7 +15,7 @@ use gfx::font_cache_thread::FontCacheThread;
 use gfx::font_context::FontContext;
 use gfx_traits::LayerId;
 use heapsize::HeapSizeOf;
-use ipc_channel::ipc::{self, IpcSender, IpcSharedMemory};
+use ipc_channel::ipc::{self, IpcSharedMemory};
 use net_traits::image::base::Image;
 use net_traits::image_cache_thread::{ImageCacheChan, ImageCacheThread, ImageResponse, ImageState};
 use net_traits::image_cache_thread::{ImageOrMetadataAvailable, UsePlaceholder};
@@ -24,7 +23,6 @@ use std::cell::{RefCell, RefMut};
 use std::collections::HashMap;
 use std::hash::BuildHasherDefault;
 use std::rc::Rc;
-use std::sync::mpsc::Sender;
 use std::sync::{Arc, Mutex, RwLock};
 use style::context::{LocalStyleContext, StyleContext};
 use style::matching::{ApplicableDeclarationsCache, StyleSharingCandidateCache};
@@ -95,9 +93,6 @@ pub struct SharedLayoutContext {
     /// The URL.
     pub url: Url,
 
-    /// A channel to send canvas renderers to paint thread, in order to correctly paint the layers
-    pub canvas_layers_sender: Mutex<Sender<(LayerId, IpcSender<CanvasMsg>)>>,
-
     /// The visible rects for each layer, as reported to us by the compositor.
     pub visible_rects: Arc<HashMap<LayerId, Rect<Au>, BuildHasherDefault<FnvHasher>>>,
 

components/layout/display_list_builder.rs

@@ -1197,13 +1197,7 @@ impl FragmentDisplayListBuilding for Fragment {
                             let (sender, receiver) = ipc::channel().unwrap();
                             ipc_renderer.send(CanvasMsg::FromLayout(
                                 FromLayoutMsg::SendData(sender))).unwrap();
-                            let data = receiver.recv().unwrap();
-
-                            // Propagate the layer and the renderer to the paint task.
-                            state.layout_context.shared.canvas_layers_sender.lock().unwrap().send(
-                                (layer_id, (*ipc_renderer).clone())).unwrap();
-
-                            data
+                            receiver.recv().unwrap()
                         },
                         None => CanvasData::Pixels(CanvasPixelData {
                             image_data: IpcSharedMemory::from_byte(0xFFu8, width * height * 4),

components/layout/layout_thread.rs

@@ -10,7 +10,6 @@
 use animation;
 use app_units::Au;
 use azure::azure::AzColor;
-use canvas_traits::CanvasMsg;
 use construct::ConstructionResult;
 use context::{LayoutContext, SharedLayoutContext, heap_size_of_local_context};
 use display_list_builder::ToGfxColor;
@@ -186,11 +185,6 @@ pub struct LayoutThread {
     /// Is this the first reflow in this LayoutThread?
     first_reflow: bool,
 
-    /// To receive a canvas renderer associated to a layer, this message is propagated
-    /// to the paint chan
-    canvas_layers_receiver: Receiver<(LayerId, IpcSender<CanvasMsg>)>,
-    canvas_layers_sender: Sender<(LayerId, IpcSender<CanvasMsg>)>,
-
     /// The workers that we use for parallel operation.
     parallel_traversal: Option<WorkQueue<SharedLayoutContext, WorkQueueData>>,
 
@@ -406,7 +400,6 @@ impl LayoutThread {
 
         // Create the channel on which new animations can be sent.
         let (new_animations_sender, new_animations_receiver) = channel();
-        let (canvas_layers_sender, canvas_layers_receiver) = channel();
 
         // Proxy IPC messages from the pipeline to the layout thread.
         let pipeline_receiver = ROUTER.route_ipc_receiver_to_new_mpsc_receiver(pipeline_port);
@@ -449,8 +442,6 @@ impl LayoutThread {
             image_cache_sender: ImageCacheChan(ipc_image_cache_sender),
             font_cache_receiver: font_cache_receiver,
             font_cache_sender: ipc_font_cache_sender,
-            canvas_layers_receiver: canvas_layers_receiver,
-            canvas_layers_sender: canvas_layers_sender,
             parallel_traversal: parallel_traversal,
             generation: 0,
             new_animations_sender: new_animations_sender,
@@ -521,7 +512,6 @@ impl LayoutThread {
             image_cache_thread: self.image_cache_thread.clone(),
             image_cache_sender: Mutex::new(self.image_cache_sender.clone()),
             font_cache_thread: Mutex::new(self.font_cache_thread.clone()),
-            canvas_layers_sender: Mutex::new(self.canvas_layers_sender.clone()),
             url: (*url).clone(),
             visible_rects: self.visible_rects.clone(),
             webrender_image_cache: self.webrender_image_cache.clone(),
@@ -1148,12 +1138,6 @@ impl LayoutThread {
             self.root_flow = self.try_get_layout_root(node);
         }
 
-        // Send new canvas renderers to the paint thread
-        while let Ok((layer_id, renderer)) = self.canvas_layers_receiver.try_recv() {
-            // Just send if there's an actual renderer
-            self.paint_chan.send(LayoutToPaintMsg::CanvasLayer(layer_id, renderer)).unwrap();
-        }
-
         // Perform post-style recalculation layout passes.
         self.perform_post_style_recalc_layout_passes(&data.reflow_info,
                                                      &mut rw_data,