fix constellation being inundated with messages from script.

script task sent RendererReadyMsg after every reflow.
now, the renderer sends RendererReady at the appropriate time,
and _only_ if it doesn't have paint permission.

src/components/gfx/render_task.rs

@@ -9,7 +9,7 @@ use azure::azure_hl::{B8G8R8A8, DrawTarget};
 use display_list::DisplayList;
 use servo_msg::compositor_msg::{RenderListener, IdleRenderState, RenderingRenderState, LayerBuffer};
 use servo_msg::compositor_msg::{LayerBufferSet, Epoch};
-use servo_msg::constellation_msg::PipelineId;
+use servo_msg::constellation_msg::{ConstellationChan, PipelineId, RendererReadyMsg};
 use font_context::FontContext;
 use geom::matrix2d::Matrix2D;
 use geom::size::Size2D;
@@ -17,8 +17,8 @@ use geom::rect::Rect;
 use opts::Opts;
 use render_context::RenderContext;
 
-use std::cell::Cell;
 use std::comm::{Chan, Port, SharedChan};
+use std::task::spawn_with;
 use extra::arc::Arc;
 
 use servo_util::time::{ProfilerChan, profile};
@@ -86,6 +86,7 @@ struct RenderTask<C,T> {
     id: PipelineId,
     port: Port<Msg<T>>,
     compositor: C,
+    constellation_chan: ConstellationChan,
     font_ctx: @mut FontContext,
     opts: Opts,
 
@@ -110,24 +111,21 @@ impl<C: RenderListener + Send,T:Send+Freeze> RenderTask<C,T> {
     pub fn create(id: PipelineId,
                   port: Port<Msg<T>>,
                   compositor: C,
+                  constellation_chan: ConstellationChan,
                   opts: Opts,
                   profiler_chan: ProfilerChan) {
-        let compositor = Cell::new(compositor);
-        let opts = Cell::new(opts);
-        let port = Cell::new(port);
-        let profiler_chan = Cell::new(profiler_chan);
 
-        do spawn {
+        do spawn_with((port, compositor, constellation_chan, opts, profiler_chan))
-            let compositor = compositor.take();
+            |(port, compositor, constellation_chan, opts, profiler_chan)| {
+
             let share_gl_context = compositor.get_gl_context();
-            let opts = opts.take();
-            let profiler_chan = profiler_chan.take();
 
             // FIXME: rust/#5967
             let mut render_task = RenderTask {
                 id: id,
-                port: port.take(),
+                port: port,
                 compositor: compositor,
+                constellation_chan: constellation_chan,
                 font_ctx: @mut FontContext::new(opts.render_backend.clone(),
                                                 false,
                                                 profiler_chan.clone()),
@@ -155,6 +153,8 @@ impl<C: RenderListener + Send,T:Send+Freeze> RenderTask<C,T> {
                     if self.paint_permission {
                         self.epoch.next();
                         self.compositor.set_layer_page_size(self.id, render_layer.size, self.epoch);
+                    } else {
+                        self.constellation_chan.send(RendererReadyMsg(self.id));
                     }
                     self.render_layer = Some(render_layer);
                     self.last_paint_msg = None;
@@ -284,6 +284,8 @@ impl<C: RenderListener + Send,T:Send+Freeze> RenderTask<C,T> {
             debug!("render_task: returning surface");
             if self.paint_permission {
                 self.compositor.paint(self.id, layer_buffer_set.clone(), self.epoch);
+            } else {
+                self.constellation_chan.send(RendererReadyMsg(self.id));
             }
             debug!("caching paint msg");
             self.last_paint_msg = Some(layer_buffer_set);

src/components/main/constellation.rs

@@ -201,20 +201,18 @@ impl NavigationContext {
     pub fn back(&mut self) -> @mut FrameTree {
         self.next.push(self.current.take_unwrap());
         self.current = Some(self.previous.pop());
-        debug!("previous: %? next: %? current: %?", self.previous, self.next, *self.current.get_ref());
         self.current.unwrap()
     }
 
     pub fn forward(&mut self) -> @mut FrameTree {
         self.previous.push(self.current.take_unwrap());
         self.current = Some(self.next.pop());
-        debug!("previous: %? next: %? current: %?", self.previous, self.next, *self.current.get_ref());
         self.current.unwrap()
     }
 
     /// Loads a new set of page frames, returning all evicted frame trees
     pub fn load(&mut self, frame_tree: @mut FrameTree) -> ~[@mut FrameTree] {
-        debug!("navigating to %?", frame_tree);
+        debug!("navigating to %?", frame_tree.pipeline.id);
         let evicted = replace(&mut self.next, ~[]);
         if self.current.is_some() {
             self.previous.push(self.current.take_unwrap());
@@ -554,7 +552,7 @@ impl Constellation {
         if url.path.ends_with(".js") {
             pipeline.execute(url);
         } else {
-            debug!("Constellation: sending load msg to %?", pipeline);
+            debug!("Constellation: sending load msg to pipeline %?", pipeline.id);
             pipeline.load(url);
         }
         let rect = self.pending_sizes.pop(&(source_pipeline_id, subpage_id));
@@ -718,12 +716,11 @@ impl Constellation {
 
                     // If to_add is not the root frame, then replace revoked_frame with it.
                     // This conveniently keeps scissor rect size intact.
-                    debug!("Constellation: replacing %? with %? in %?", revoke_id, to_add, next_frame_tree);
+                    debug!("Constellation: replacing %? with %? in %?",
+                        revoke_id, to_add.pipeline.id, next_frame_tree.pipeline.id);
                     if to_add.parent.is_some() {
-                        let replaced = next_frame_tree.replace_child(revoke_id, to_add);
+                        next_frame_tree.replace_child(revoke_id, to_add);
-                        debug!("Replaced child: %?", replaced);
                     }
-                    debug!("Constellation: frame tree after replacing: %?", next_frame_tree);
                 }
 
                 None => {

src/components/main/pipeline.rs

@@ -54,6 +54,7 @@ impl Pipeline {
         RenderTask::create(id,
                            render_port,
                            compositor_chan.clone(),
+                           constellation_chan.clone(),
                            opts.clone(),
                            profiler_chan.clone());
 
@@ -136,6 +137,7 @@ impl Pipeline {
             RenderTask::create(id,
                                render_port,
                                compositor_chan.clone(),
+                               constellation_chan.clone(),
                                opts.clone(),
                                profiler_chan.clone());
 

src/components/script/script_task.rs

@@ -21,7 +21,7 @@ use layout_interface::{ReflowDocumentDamage, ReflowForDisplay, ReflowGoal};
 use layout_interface::ReflowMsg;
 use layout_interface;
 use servo_msg::constellation_msg::{ConstellationChan, LoadUrlMsg, NavigationDirection};
-use servo_msg::constellation_msg::{PipelineId, SubpageId, RendererReadyMsg};
+use servo_msg::constellation_msg::{PipelineId, SubpageId};
 use servo_msg::constellation_msg::{LoadIframeUrlMsg, IFrameSandboxed, IFrameUnsandboxed};
 use servo_msg::constellation_msg;
 
@@ -582,7 +582,6 @@ impl ScriptTask {
         if page_tree.page.last_reflow_id == reflow_id {
             page_tree.page.layout_join_port = None;
         }
-        self.constellation_chan.send(RendererReadyMsg(pipeline_id));
         self.compositor.set_ready_state(FinishedLoading);
     }