From 2e40baba095b72f3df086ab5c59e2cab888c2676 Mon Sep 17 00:00:00 2001
From: Cameron Zwarich <zwarich@mozilla.com>
Date: Sat, 19 Jul 2014 20:14:42 -0700
Subject: [PATCH] Always create CompositorData with a new layer

Since it makes no sense to create one without the other, the public
interface shouldn't let you do anything else.
---
 src/components/compositing/compositor.rs      | 13 ++++------
 src/components/compositing/compositor_data.rs | 24 +++++++++----------
 2 files changed, 17 insertions(+), 20 deletions(-)

diff --git a/src/components/compositing/compositor.rs b/src/components/compositing/compositor.rs
index 0402661f6aa..affbc4cdda7 100644
--- a/src/components/compositing/compositor.rs
+++ b/src/components/compositing/compositor.rs
@@ -31,7 +31,6 @@ use layers::layers::LayerBufferSet;
 use layers::rendergl;
 use layers::rendergl::RenderContext;
 use layers::scene::Scene;
-use layers::layers::Layer;
 use opengles::gl2;
 use png;
 use servo_msg::compositor_msg::{Blank, Epoch, FixedPosition, FinishedLoading, IdleRenderState};
@@ -369,16 +368,14 @@ impl IOCompositor {
                 pipeline_id: root_pipeline.id,
                 epoch: layer_properties.epoch,
                 id: LayerId::null(),
-                rect: Rect::zero(),
+                rect: layer_properties.rect,
                 background_color: layer_properties.background_color,
                 scroll_policy: FixedPosition,
             };
-            let new_compositor_data = CompositorData::new(root_pipeline,
-                                                          root_properties,
-                                                          WantsScrollEvents);
-            let new_root = Rc::new(Layer::new(layer_properties.rect,
-                                              self.opts.tile_size,
-                                              new_compositor_data));
+            let new_root = CompositorData::new_layer(root_pipeline,
+                                                     root_properties,
+                                                     WantsScrollEvents,
+                                                     self.opts.tile_size);
 
             CompositorData::add_child(new_root.clone(), layer_properties);
 
diff --git a/src/components/compositing/compositor_data.rs b/src/components/compositing/compositor_data.rs
index abcbb5e6fd9..0efc3585377 100644
--- a/src/components/compositing/compositor_data.rs
+++ b/src/components/compositing/compositor_data.rs
@@ -52,11 +52,12 @@ pub enum WantsScrollEventsFlag {
 }
 
 impl CompositorData {
-    pub fn new(pipeline: CompositionPipeline,
-               layer_properties: LayerProperties,
-               wants_scroll_events: WantsScrollEventsFlag)
-               -> CompositorData {
-        CompositorData {
+    pub fn new_layer(pipeline: CompositionPipeline,
+                     layer_properties: LayerProperties,
+                     wants_scroll_events: WantsScrollEventsFlag,
+                     tile_size: uint)
+                     -> Rc<Layer<CompositorData>> {
+        let new_compositor_data = CompositorData {
             pipeline: pipeline,
             id: layer_properties.id,
             scroll_offset: TypedPoint2D(0f32, 0f32),
@@ -64,7 +65,8 @@ impl CompositorData {
             scroll_policy: layer_properties.scroll_policy,
             background_color: layer_properties.background_color,
             epoch: layer_properties.epoch,
-        }
+        };
+        Rc::new(Layer::new(layer_properties.rect, tile_size, new_compositor_data))
     }
 
     /// Adds a child layer to the layer with the given ID and the given pipeline, if it doesn't
@@ -72,12 +74,10 @@ impl CompositorData {
     /// painting status as its parent.
     pub fn add_child(layer: Rc<Layer<CompositorData>>,
                      layer_properties: LayerProperties) {
-        let new_compositor_data = CompositorData::new(layer.extra_data.borrow().pipeline.clone(),
-                                                      layer_properties,
-                                                      DoesntWantScrollEvents);
-        let new_kid = Rc::new(Layer::new(layer_properties.rect,
-                                         layer.tile_size,
-                                         new_compositor_data));
+        let new_kid = CompositorData::new_layer(layer.extra_data.borrow().pipeline.clone(),
+                                                layer_properties,
+                                                DoesntWantScrollEvents,
+                                                layer.tile_size);
         layer.add_child(new_kid.clone());
     }