Auto merge of #24333 - mmatyas:webgl_fns_samplers, r=jdm

Add WebGLSampler support

Reference: https://www.khronos.org/registry/webgl/specs/latest/2.0/#3.7.13

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cc @jdm @zakorgy

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components/script/dom/mod.rs

@@ -525,6 +525,7 @@ pub mod webglprogram;
 pub mod webglquery;
 pub mod webglrenderbuffer;
 pub mod webglrenderingcontext;
+pub mod webglsampler;
 pub mod webglshader;
 pub mod webglshaderprecisionformat;
 pub mod webglsync;