Auto merge of #15186 - servo:re-revert, r=mbrubeck

Re revert the backed out PRs

r? anyone

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6 files changed, 58 insertions, 45 deletions

diff --git a/components/compositing/compositor.rs b/components/compositing/compositor.rs
index 6d00a31a944..49b92f8e171 100644
--- a/components/compositing/compositor.rs
+++ b/components/compositing/compositor.rs
@@ -342,15 +342,13 @@ fn initialize_png(width: usize, height: usize) -> RenderTargetInfo {
 
 struct RenderNotifier {
     compositor_proxy: Box<CompositorProxy>,
-    constellation_chan: Sender<ConstellationMsg>,
 }
 
 impl RenderNotifier {
     fn new(compositor_proxy: Box<CompositorProxy>,
-           constellation_chan: Sender<ConstellationMsg>) -> RenderNotifier {
+           _: Sender<ConstellationMsg>) -> RenderNotifier {
         RenderNotifier {
             compositor_proxy: compositor_proxy,
-            constellation_chan: constellation_chan,
         }
     }
 }
@@ -365,16 +363,8 @@ impl webrender_traits::RenderNotifier for RenderNotifier {
     }
 
     fn pipeline_size_changed(&mut self,
-                             pipeline_id: webrender_traits::PipelineId,
-                             size: Option<webrender_traits::LayoutSize>) {
-        let pipeline_id = pipeline_id.from_webrender();
-
-        if let Some(size) = size {
-            let msg = ConstellationMsg::FrameSize(pipeline_id, size.to_untyped());
-            if let Err(e) = self.constellation_chan.send(msg) {
-                warn!("Compositor resize to constellation failed ({}).", e);
-            }
-        }
+                             _: webrender_traits::PipelineId,
+                             _: Option<webrender_traits::LayoutSize>) {
     }
 }
 
diff --git a/components/constellation/constellation.rs b/components/constellation/constellation.rs
index e3aefdeaa46..132bf40e1ac 100644
--- a/components/constellation/constellation.rs
+++ b/components/constellation/constellation.rs
@@ -817,12 +817,6 @@ impl<Message, LTF, STF> Constellation<Message, LTF, STF>
                 debug!("constellation exiting");
                 self.handle_exit();
             }
-            // The compositor discovered the size of a subframe. This needs to be reflected by all
-            // frame trees in the navigation context containing the subframe.
-            FromCompositorMsg::FrameSize(pipeline_id, size) => {
-                debug!("constellation got frame size message");
-                self.handle_frame_size_msg(pipeline_id, &TypedSize2D::from_untyped(&size));
-            }
             FromCompositorMsg::GetFrame(pipeline_id, resp_chan) => {
                 debug!("constellation got get root pipeline message");
                 self.handle_get_frame(pipeline_id, resp_chan);
@@ -1089,6 +1083,12 @@ impl<Message, LTF, STF> Constellation<Message, LTF, STF>
             FromLayoutMsg::ChangeRunningAnimationsState(pipeline_id, animation_state) => {
                 self.handle_change_running_animations_state(pipeline_id, animation_state)
             }
+            // Layout sends new sizes for all subframes. This needs to be reflected by all
+            // frame trees in the navigation context containing the subframe.
+            FromLayoutMsg::FrameSizes(iframe_sizes) => {
+                debug!("constellation got frame size message");
+                self.handle_frame_size_msg(iframe_sizes);
+            }
             FromLayoutMsg::SetCursor(cursor) => {
                 self.handle_set_cursor_msg(cursor)
             }
@@ -1327,30 +1327,30 @@ impl<Message, LTF, STF> Constellation<Message, LTF, STF>
     }
 
     fn handle_frame_size_msg(&mut self,
-                             pipeline_id: PipelineId,
-                             size: &TypedSize2D<f32, PagePx>) {
-        let msg = ConstellationControlMsg::Resize(pipeline_id, WindowSizeData {
-            visible_viewport: *size,
-            initial_viewport: *size * ScaleFactor::new(1.0),
-            device_pixel_ratio: self.window_size.device_pixel_ratio,
-        }, WindowSizeType::Initial);
-
-        // Store the new rect inside the pipeline
-        let result = {
-            // Find the pipeline that corresponds to this rectangle. It's possible that this
-            // pipeline may have already exited before we process this message, so just
-            // early exit if that occurs.
-            match self.pipelines.get_mut(&pipeline_id) {
-                Some(pipeline) => {
-                    pipeline.size = Some(*size);
-                    pipeline.event_loop.send(msg)
+                             iframe_sizes: Vec<(PipelineId, TypedSize2D<f32, PagePx>)>) {
+        for (pipeline_id, size) in iframe_sizes {
+            let result = {
+                let pipeline = match self.pipelines.get_mut(&pipeline_id) {
+                    Some(pipeline) => pipeline,
+                    None => continue,
+                };
+
+                if pipeline.size == Some(size) {
+                    continue;
                 }
-                None => return,
-            }
-        };
 
-        if let Err(e) = result {
-            self.handle_send_error(pipeline_id, e);
+                pipeline.size = Some(size);
+                let msg = ConstellationControlMsg::Resize(pipeline_id, WindowSizeData {
+                    visible_viewport: size,
+                    initial_viewport: size * ScaleFactor::new(1.0),
+                    device_pixel_ratio: self.window_size.device_pixel_ratio,
+                }, WindowSizeType::Initial);
+
+                pipeline.event_loop.send(msg)
+            };
+            if let Err(e) = result {
+                self.handle_send_error(pipeline_id, e);
+            }
         }
     }
 
diff --git a/components/layout/display_list_builder.rs b/components/layout/display_list_builder.rs
index fa5126471d3..107e6cad360 100644
--- a/components/layout/display_list_builder.rs
+++ b/components/layout/display_list_builder.rs
@@ -14,7 +14,7 @@ use app_units::{AU_PER_PX, Au};
 use block::{BlockFlow, BlockStackingContextType};
 use canvas_traits::{CanvasData, CanvasMsg, FromLayoutMsg};
 use context::SharedLayoutContext;
-use euclid::{Point2D, Rect, SideOffsets2D, Size2D};
+use euclid::{Point2D, Rect, SideOffsets2D, Size2D, TypedSize2D};
 use flex::FlexFlow;
 use flow::{BaseFlow, Flow, IS_ABSOLUTELY_POSITIONED};
 use flow_ref::FlowRef;
@@ -32,6 +32,7 @@ use inline::{FIRST_FRAGMENT_OF_ELEMENT, InlineFlow, LAST_FRAGMENT_OF_ELEMENT};
 use ipc_channel::ipc;
 use list_item::ListItemFlow;
 use model::{self, MaybeAuto};
+use msg::constellation_msg::PipelineId;
 use net_traits::image::base::PixelFormat;
 use net_traits::image_cache_thread::UsePlaceholder;
 use range::Range;
@@ -56,6 +57,7 @@ use style::servo::restyle_damage::REPAINT;
 use style::values::{RGBA, computed};
 use style::values::computed::{AngleOrCorner, Gradient, GradientKind, LengthOrPercentage, LengthOrPercentageOrAuto};
 use style::values::specified::{HorizontalDirection, VerticalDirection};
+use style_traits::PagePx;
 use style_traits::cursor::Cursor;
 use table_cell::CollapsedBordersForCell;
 use webrender_traits::{ColorF, GradientStop, ScrollPolicy};
@@ -105,6 +107,10 @@ pub struct DisplayListBuildState<'a> {
     /// The current scroll root id, used to keep track of state when
     /// recursively building and processing the display list.
     pub current_scroll_root_id: ScrollRootId,
+
+    /// Vector containing iframe sizes, used to inform the constellation about
+    /// new iframe sizes
+    pub iframe_sizes: Vec<(PipelineId, TypedSize2D<f32, PagePx>)>,
 }
 
 impl<'a> DisplayListBuildState<'a> {
@@ -118,6 +124,7 @@ impl<'a> DisplayListBuildState<'a> {
             processing_scroll_root_element: false,
             current_stacking_context_id: StackingContextId::root(),
             current_scroll_root_id: ScrollRootId::root(),
+            iframe_sizes: Vec::new(),
         }
     }
 
@@ -1443,6 +1450,10 @@ impl FragmentDisplayListBuilding for Fragment {
                         iframe: fragment_info.pipeline_id,
                     });
 
+                    let size = Size2D::new(item.bounds().size.width.to_f32_px(),
+                                           item.bounds().size.height.to_f32_px());
+                    state.iframe_sizes.push((fragment_info.pipeline_id, TypedSize2D::from_untyped(&size)));
+
                     state.add_display_item(item);
                 }
             }
diff --git a/components/layout_thread/lib.rs b/components/layout_thread/lib.rs
index caabb158f5d..8297c6a725c 100644
--- a/components/layout_thread/lib.rs
+++ b/components/layout_thread/lib.rs
@@ -933,6 +933,17 @@ impl LayoutThread {
                         let origin = Rect::new(Point2D::new(Au(0), Au(0)), root_size);
                         build_state.root_stacking_context.bounds = origin;
                         build_state.root_stacking_context.overflow = origin;
+
+                        if !build_state.iframe_sizes.is_empty() {
+                            // build_state.iframe_sizes is only used here, so its okay to replace
+                            // it with an empty vector
+                            let iframe_sizes = std::mem::replace(&mut build_state.iframe_sizes, vec![]);
+                            let msg = ConstellationMsg::FrameSizes(iframe_sizes);
+                            if let Err(e) = self.constellation_chan.send(msg) {
+                                warn!("Layout resize to constellation failed ({}).", e);
+                            }
+                        }
+
                         rw_data.display_list = Some(Arc::new(build_state.to_display_list()));
                     }
                     (ReflowGoal::ForScriptQuery, false) => {}
diff --git a/components/script_traits/lib.rs b/components/script_traits/lib.rs
index c0131158326..295000380ca 100644
--- a/components/script_traits/lib.rs
+++ b/components/script_traits/lib.rs
@@ -696,8 +696,6 @@ pub enum WebDriverCommandMsg {
 pub enum ConstellationMsg {
     /// Exit the constellation.
     Exit,
-    /// Inform the constellation of the size of the viewport.
-    FrameSize(PipelineId, Size2D<f32>),
     /// Request that the constellation send the FrameId corresponding to the document
     /// with the provided pipeline id
     GetFrame(PipelineId, IpcSender<Option<FrameId>>),
diff --git a/components/script_traits/script_msg.rs b/components/script_traits/script_msg.rs
index fc29563cbbd..d35e23a7bb9 100644
--- a/components/script_traits/script_msg.rs
+++ b/components/script_traits/script_msg.rs
@@ -15,7 +15,7 @@ use WorkerScriptLoadOrigin;
 use canvas_traits::CanvasMsg;
 use devtools_traits::{ScriptToDevtoolsControlMsg, WorkerId};
 use euclid::point::Point2D;
-use euclid::size::Size2D;
+use euclid::size::{Size2D, TypedSize2D};
 use gfx_traits::ScrollRootId;
 use ipc_channel::ipc::IpcSender;
 use msg::constellation_msg::{FrameId, PipelineId, TraversalDirection};
@@ -24,6 +24,7 @@ use net_traits::CoreResourceMsg;
 use net_traits::storage_thread::StorageType;
 use offscreen_gl_context::{GLContextAttributes, GLLimits};
 use servo_url::ServoUrl;
+use style_traits::PagePx;
 use style_traits::cursor::Cursor;
 use style_traits::viewport::ViewportConstraints;
 
@@ -32,6 +33,8 @@ use style_traits::viewport::ViewportConstraints;
 pub enum LayoutMsg {
     /// Indicates whether this pipeline is currently running animations.
     ChangeRunningAnimationsState(PipelineId, AnimationState),
+    /// Inform the constellation of the size of the pipeline's viewport.
+    FrameSizes(Vec<(PipelineId, TypedSize2D<f32, PagePx>)>),
     /// Requests that the constellation inform the compositor of the a cursor change.
     SetCursor(Cursor),
     /// Notifies the constellation that the viewport has been constrained in some manner