Auto merge of #6770 - ecoal95:webgl-again, r=jdm

Add multiple WebGL calls and improve error detection

Since it probably won't merge until multiprocess lands, I plan to use this PR to keep improving WebGL support until it can land.

Main TODOs are integration of tests, since it seems https://github.com/KhronosGroup/WebGL/issues/1105 is going nowhere, adding missing calls and proper painting via native surfaces instead of readback.

I can't resolve conflicts right now because of time but I will do it soon.

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1 files changed, 16 insertions, 0 deletions

diff --git a/components/script/dom/htmlcanvaselement.rs b/components/script/dom/htmlcanvaselement.rs
index 4823f881be7..83e8397d859 100644
--- a/components/script/dom/htmlcanvaselement.rs
+++ b/components/script/dom/htmlcanvaselement.rs
@@ -159,6 +159,7 @@ pub trait HTMLCanvasElementHelpers {
     fn get_or_init_webgl_context(self,
                                  cx: *mut JSContext,
                                  attrs: Option<HandleValue>) -> Option<Root<WebGLRenderingContext>>;
+
     fn is_valid(self) -> bool;
 }
 
@@ -325,3 +326,18 @@ impl<'a> From<&'a WebGLContextAttributes> for GLContextAttributes {
     }
 }
 
+pub mod utils {
+    use dom::window::Window;
+    use ipc_channel::ipc;
+    use net_traits::image_cache_task::{ImageCacheChan, ImageResponse};
+    use url::Url;
+
+    pub fn request_image_from_cache(window: &Window, url: Url) -> ImageResponse {
+        let image_cache = window.image_cache_task();
+        let (response_chan, response_port) = ipc::channel().unwrap();
+        image_cache.request_image(url, ImageCacheChan(response_chan), None);
+        let result = response_port.recv().unwrap();
+        result.image_response
+    }
+}
+