Auto merge of #9589 - glennw:webrender, r=pcwalton

Add WebRender integration to Servo.

WebRender is an experimental GPU accelerated rendering backend for Servo.

The WebRender backend can be specified by running Servo with the -w option (otherwise the default rendering backend will be used).

WebRender has many bugs, and missing features - but it is usable to browse most websites - please report any WebRender specific rendering bugs you encounter!

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2 files changed, 12 insertions, 3 deletions

diff --git a/components/script/dom/htmlcanvaselement.rs b/components/script/dom/htmlcanvaselement.rs
index 3ab122d2bf7..0288efc206a 100644
--- a/components/script/dom/htmlcanvaselement.rs
+++ b/components/script/dom/htmlcanvaselement.rs
@@ -2,7 +2,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-use canvas_traits::{CanvasMsg, FromLayoutMsg};
+use canvas_traits::{CanvasMsg, FromLayoutMsg, CanvasData};
 use dom::attr::Attr;
 use dom::attr::AttrValue;
 use dom::bindings::cell::DOMRefCell;
@@ -202,10 +202,17 @@ impl HTMLCanvasElement {
 
         let data = if let Some(renderer) = self.ipc_renderer() {
             let (sender, receiver) = ipc::channel().unwrap();
-            let msg = CanvasMsg::FromLayout(FromLayoutMsg::SendPixelContents(sender));
+            let msg = CanvasMsg::FromLayout(FromLayoutMsg::SendData(sender));
             renderer.send(msg).unwrap();
 
-            receiver.recv().unwrap().to_vec()
+            match receiver.recv().unwrap() {
+                CanvasData::Pixels(pixel_data)
+                    => pixel_data.image_data.to_vec(),
+                CanvasData::WebGL(_)
+                    // TODO(ecoal95): Not sure if WebGL canvas is required for 2d spec,
+                    // but I think it's not.
+                    => return None,
+            }
         } else {
             repeat(0xffu8).take((size.height as usize) * (size.width as usize) * 4).collect()
         };
diff --git a/components/script/dom/webglrenderingcontext.rs b/components/script/dom/webglrenderingcontext.rs
index ff2d6968e9a..aba9e32b45f 100644
--- a/components/script/dom/webglrenderingcontext.rs
+++ b/components/script/dom/webglrenderingcontext.rs
@@ -72,6 +72,7 @@ pub struct WebGLRenderingContext {
     #[ignore_heap_size_of = "Defined in ipc-channel"]
     ipc_renderer: IpcSender<CanvasMsg>,
     canvas: JS<HTMLCanvasElement>,
+    #[ignore_heap_size_of = "Defined in webrender_traits"]
     last_error: Cell<Option<WebGLError>>,
     texture_unpacking_settings: Cell<TextureUnpacking>,
     bound_texture_2d: MutNullableHeap<JS<WebGLTexture>>,
@@ -462,6 +463,7 @@ impl WebGLRenderingContextMethods for WebGLRenderingContext {
             Some(data) => data,
             None => return self.webgl_error(InvalidValue),
         };
+
         if offset < 0 {
             return self.webgl_error(InvalidValue);
         }