Auto merge of #18114 - emilio:revert-webgl-refactor, r=nox

Revert "Auto merge of #17891 - MortimerGoro:webgl_move, r=glennw,emilio"

This reverts commit 90f55ea4580e2a15f7d70d0491444f18b972d450, reversing
changes made to 2e60b27a2186a8cba4b952960155dfcf3f47d7db.

Doing that per Josh's request, since it's causing very frequent intermittent OOMs on the android builders.

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3 files changed, 12 insertions, 5 deletions

diff --git a/components/script_traits/Cargo.toml b/components/script_traits/Cargo.toml
index 2c083b2773c..70fcdbb3f33 100644
--- a/components/script_traits/Cargo.toml
+++ b/components/script_traits/Cargo.toml
@@ -25,6 +25,7 @@ libc = "0.2"
 metrics = {path = "../metrics"}
 msg = {path = "../msg"}
 net_traits = {path = "../net_traits"}
+offscreen_gl_context = { version = "0.11", features = ["serde"] }
 profile_traits = {path = "../profile_traits"}
 rustc-serialize = "0.3.4"
 serde = "1.0"
diff --git a/components/script_traits/lib.rs b/components/script_traits/lib.rs
index 4a197e759ff..85122d35c3c 100644
--- a/components/script_traits/lib.rs
+++ b/components/script_traits/lib.rs
@@ -24,6 +24,7 @@ extern crate ipc_channel;
 extern crate libc;
 extern crate msg;
 extern crate net_traits;
+extern crate offscreen_gl_context;
 extern crate profile_traits;
 extern crate rustc_serialize;
 #[macro_use] extern crate serde;
@@ -38,7 +39,6 @@ mod script_msg;
 pub mod webdriver_msg;
 
 use bluetooth_traits::BluetoothRequest;
-use canvas_traits::webgl::WebGLPipeline;
 use devtools_traits::{DevtoolScriptControlMsg, ScriptToDevtoolsControlMsg, WorkerId};
 use euclid::{Size2D, Length, Point2D, Vector2D, Rect, ScaleFactor, TypedSize2D};
 use gfx_traits::Epoch;
@@ -524,10 +524,8 @@ pub struct InitialScriptState {
     pub pipeline_namespace_id: PipelineNamespaceId,
     /// A ping will be sent on this channel once the script thread shuts down.
     pub content_process_shutdown_chan: IpcSender<()>,
-    /// A channel to the webgl thread used in this pipeline.
-    pub webgl_chan: WebGLPipeline,
     /// A channel to the webvr thread, if available.
-    pub webvr_chan: Option<IpcSender<WebVRMsg>>
+    pub webvr_thread: Option<IpcSender<WebVRMsg>>
 }
 
 /// This trait allows creating a `ScriptThread` without depending on the `script`
@@ -761,6 +759,8 @@ pub enum ConstellationMsg {
     Reload(TopLevelBrowsingContextId),
     /// A log entry, with the top-level browsing context id and thread name
     LogEntry(Option<TopLevelBrowsingContextId>, Option<String>, LogEntry),
+    /// Set the WebVR thread channel.
+    SetWebVRThread(IpcSender<WebVRMsg>),
     /// Dispatch WebVR events to the subscribed script threads.
     WebVREvents(Vec<PipelineId>, Vec<WebVREvent>),
     /// Create a new top level browsing context.
diff --git a/components/script_traits/script_msg.rs b/components/script_traits/script_msg.rs
index 156f85a2be7..4fd8fca5c7f 100644
--- a/components/script_traits/script_msg.rs
+++ b/components/script_traits/script_msg.rs
@@ -12,7 +12,7 @@ use LoadData;
 use MozBrowserEvent;
 use WorkerGlobalScopeInit;
 use WorkerScriptLoadOrigin;
-use canvas_traits::canvas::CanvasMsg;
+use canvas_traits::CanvasMsg;
 use devtools_traits::{ScriptToDevtoolsControlMsg, WorkerId};
 use euclid::{Point2D, Size2D, TypedSize2D};
 use ipc_channel::ipc::IpcSender;
@@ -21,6 +21,7 @@ use msg::constellation_msg::{Key, KeyModifiers, KeyState};
 use net_traits::CoreResourceMsg;
 use net_traits::request::RequestInit;
 use net_traits::storage_thread::StorageType;
+use offscreen_gl_context::{GLContextAttributes, GLLimits};
 use servo_url::ImmutableOrigin;
 use servo_url::ServoUrl;
 use style_traits::CSSPixel;
@@ -77,6 +78,11 @@ pub enum ScriptMsg {
     /// Requests that a new 2D canvas thread be created. (This is done in the constellation because
     /// 2D canvases may use the GPU and we don't want to give untrusted content access to the GPU.)
     CreateCanvasPaintThread(Size2D<i32>, IpcSender<IpcSender<CanvasMsg>>),
+    /// Requests that a new WebGL thread be created. (This is done in the constellation because
+    /// WebGL uses the GPU and we don't want to give untrusted content access to the GPU.)
+    CreateWebGLPaintThread(Size2D<i32>,
+                           GLContextAttributes,
+                           IpcSender<Result<(IpcSender<CanvasMsg>, GLLimits), String>>),
     /// Notifies the constellation that this frame has received focus.
     Focus,
     /// Forward an event that was sent to the parent window.