Auto merge of #12202 - peterjoel:issue_8509, r=nox

DOMMatrix and DOMMatrixReadOnly

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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 #8509.

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components/script/dom/bindings/trace.rs

@@ -41,9 +41,8 @@ use dom::bindings::reflector::{Reflectable, Reflector};
 use dom::bindings::str::{DOMString, USVString};
 use dom::bindings::utils::WindowProxyHandler;
 use encoding::types::EncodingRef;
+use euclid::{Matrix2D, Matrix4D, Point2D};
 use euclid::length::Length as EuclidLength;
-use euclid::matrix2d::Matrix2D;
-use euclid::point::Point2D;
 use euclid::rect::Rect;
 use euclid::size::Size2D;
 use html5ever::tree_builder::QuirksMode;
@@ -320,6 +319,7 @@ no_jsmanaged_fields!(LengthOrPercentageOrAuto);
 no_jsmanaged_fields!(RGBA);
 no_jsmanaged_fields!(EuclidLength<Unit, T>);
 no_jsmanaged_fields!(Matrix2D<T>);
+no_jsmanaged_fields!(Matrix4D<T>);
 no_jsmanaged_fields!(StorageType);
 no_jsmanaged_fields!(CanvasGradientStop, LinearGradientStyle, RadialGradientStyle);
 no_jsmanaged_fields!(LineCapStyle, LineJoinStyle, CompositionOrBlending);