Auto merge of #6546 - michaelwu:slim-layoutdatawrapper, r=Ms2ger

Remove LayoutChan from LayoutDataWrapper

Saves 32 bytes in Node.

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components/layout/data.rs

@@ -7,7 +7,6 @@ use incremental::RestyleDamage;
 use msg::constellation_msg::ConstellationChan;
 use parallel::DomParallelInfo;
 use script::dom::node::SharedLayoutData;
-use script::layout_interface::LayoutChan;
 use std::sync::Arc;
 use style::properties::ComputedValues;
 
@@ -61,7 +60,6 @@ bitflags! {
 }
 
 pub struct LayoutDataWrapper {
-    pub chan: Option<LayoutChan>,
     pub shared_data: SharedLayoutData,
     pub data: Box<PrivateLayoutData>,
 }

components/layout/traversal.rs

@@ -132,7 +132,7 @@ impl<'a> PreorderDomTraversal for RecalcStyleForNode<'a> {
         //
         // FIXME(pcwalton): Stop allocating here. Ideally this should just be done by the HTML
         // parser.
-        node.initialize_layout_data(self.layout_context.shared.layout_chan.clone());
+        node.initialize_layout_data();
 
         // Get the parent node.
         let parent_opt = node.layout_parent_node(self.layout_context.shared);

components/layout/wrapper.rs

@@ -56,7 +56,6 @@ use script::dom::node::{Node, NodeTypeId};
 use script::dom::node::{LayoutNodeHelpers, RawLayoutNodeHelpers, SharedLayoutData};
 use script::dom::node::{HAS_CHANGED, IS_DIRTY, HAS_DIRTY_SIBLINGS, HAS_DIRTY_DESCENDANTS};
 use script::dom::text::Text;
-use script::layout_interface::LayoutChan;
 use smallvec::VecLike;
 use msg::constellation_msg::{PipelineId, SubpageId};
 use util::str::is_whitespace;
@@ -179,12 +178,11 @@ impl<'ln> LayoutNode<'ln> {
     /// Resets layout data and styles for the node.
     ///
     /// FIXME(pcwalton): Do this as part of fragment building instead of in a traversal.
-    pub fn initialize_layout_data(self, chan: LayoutChan) {
+    pub fn initialize_layout_data(self) {
         let mut layout_data_ref = self.mutate_layout_data();
         match *layout_data_ref {
             None => {
                 *layout_data_ref = Some(LayoutDataWrapper {
-                    chan: Some(chan),
                     shared_data: SharedLayoutData { style: None },
                     data: box PrivateLayoutData::new(),
                 });

components/script/dom/node.rs

@@ -191,7 +191,7 @@ impl NodeFlags {
 impl Drop for Node {
     #[allow(unsafe_code)]
     fn drop(&mut self) {
-        self.layout_data.dispose();
+        self.layout_data.dispose(self);
     }
 }
 
@@ -212,7 +212,6 @@ pub struct SharedLayoutData {
 
 /// Encapsulates the abstract layout data.
 pub struct LayoutData {
-    chan: Option<LayoutChan>,
     _shared_data: SharedLayoutData,
     _data: NonZero<*const ()>,
 }
@@ -234,17 +233,12 @@ impl LayoutDataRef {
     }
 
     /// Sends layout data, if any, back to the layout task to be destroyed.
-    pub fn dispose(&self) {
+    pub fn dispose(&self, node: &Node) {
         debug_assert!(task_state::get().is_script());
-        if let Some(mut layout_data) = mem::replace(&mut *self.data_cell.borrow_mut(), None) {
-            let layout_chan = layout_data.chan.take();
-            match layout_chan {
-                None => {}
-                Some(chan) => {
-                    let LayoutChan(chan) = chan;
-                    chan.send(Msg::ReapLayoutData(layout_data)).unwrap()
-                }
-            }
+        if let Some(layout_data) = mem::replace(&mut *self.data_cell.borrow_mut(), None) {
+            let win = window_from_node(node);
+            let LayoutChan(chan) = win.layout_chan();
+            chan.send(Msg::ReapLayoutData(layout_data)).unwrap()
         }
     }
 
@@ -317,7 +311,7 @@ impl<'a> PrivateNodeHelpers for &'a Node {
             node.r().set_flag(IS_IN_DOC, false);
             vtable_for(&node.r()).unbind_from_tree(parent_in_doc);
         }
-        self.layout_data.dispose();
+        self.layout_data.dispose(self);
     }
 
     //
@@ -535,7 +529,7 @@ pub trait NodeHelpers {
 
 impl<'a> NodeHelpers for &'a Node {
     fn teardown(self) {
-        self.layout_data.dispose();
+        self.layout_data.dispose(self);
         for kid in self.children() {
             kid.r().teardown();
         }

tests/unit/script/size_of.rs

@@ -39,10 +39,10 @@ macro_rules! sizeof_checker (
 
 // Update the sizes here
 sizeof_checker!(size_event_target, EventTarget, 48);
-sizeof_checker!(size_node, Node, 216);
-sizeof_checker!(size_element, Element, 328);
-sizeof_checker!(size_htmlelement, HTMLElement, 344);
-sizeof_checker!(size_div, HTMLDivElement, 344);
-sizeof_checker!(size_span, HTMLSpanElement, 344);
-sizeof_checker!(size_text, Text, 248);
-sizeof_checker!(size_characterdata, CharacterData, 248);
+sizeof_checker!(size_node, Node, 184);
+sizeof_checker!(size_element, Element, 296);
+sizeof_checker!(size_htmlelement, HTMLElement, 312);
+sizeof_checker!(size_div, HTMLDivElement, 312);
+sizeof_checker!(size_span, HTMLSpanElement, 312);
+sizeof_checker!(size_text, Text, 216);
+sizeof_checker!(size_characterdata, CharacterData, 216);