Auto merge of #18177 - MortimerGoro:oes_standard_derivatives, r=emilio

Implement WebGL OES_standard_derivatives extension.

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Implement WebGL OES_standard_derivatives extension. Some Three.js 3D models fail to render because of the lack of this extension.

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components/script/dom/webidls/OESStandardDerivatives.webidl

@@ -0,0 +1,12 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * 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/. */
+/*
+ * WebGL IDL definitions from the Khronos specification:
+ * https://www.khronos.org/registry/webgl/extensions/OES_standard_derivatives/
+ */
+
+[NoInterfaceObject]
+interface OESStandardDerivatives {
+    const GLenum FRAGMENT_SHADER_DERIVATIVE_HINT_OES = 0x8B8B;
+};