Auto merge of #21543 - ceyusa:wip-player, r=<try>

Add <audio> and <video> player backends

These patches enables audio and video playing inside Servo.

It is bit hackish way to enable it, thus the purpose of this pull request is for an early request for comments.

It is tested with the current servo-media GStreamer backend in Linux.

~~The produced layout is not correct, since the elements after the video seems to be stacked behind, and the same with the scrolling bars.~~

~~There is no JavaScript interface yet~~, neither controls.

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- [X] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [X] These changes fix #6711

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1 files changed, 3 insertions, 1 deletions

diff --git a/components/script_traits/lib.rs b/components/script_traits/lib.rs
index 6c087690b5f..802e61ea172 100644
--- a/components/script_traits/lib.rs
+++ b/components/script_traits/lib.rs
@@ -72,7 +72,7 @@ use style_traits::CSSPixel;
 use style_traits::SpeculativePainter;
 use style_traits::cursor::CursorKind;
 use webdriver_msg::{LoadStatus, WebDriverScriptCommand};
-use webrender_api::{ExternalScrollId, DevicePixel, DeviceUintSize, DocumentId, ImageKey};
+use webrender_api::{DevicePixel, DeviceUintSize, DocumentId, ExternalScrollId, ImageKey, RenderApiSender};
 use webvr_traits::{WebVREvent, WebVRMsg};
 
 pub use script_msg::{LayoutMsg, ScriptMsg, EventResult, LogEntry};
@@ -588,6 +588,8 @@ pub struct InitialScriptState {
     pub webvr_chan: Option<IpcSender<WebVRMsg>>,
     /// The Webrender document ID associated with this thread.
     pub webrender_document: DocumentId,
+    /// FIXME(victor): The Webrender API sender in this constellation's pipeline
+    pub webrender_api_sender: RenderApiSender,
 }
 
 /// This trait allows creating a `ScriptThread` without depending on the `script`