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/webidls/WebGL2RenderingContext.webidl

@@ -530,13 +530,13 @@ interface mixin WebGL2RenderingContextBase
   any getQueryParameter(WebGLQuery query, GLenum pname);
 
   /* Sampler Objects */
-  /*WebGLSampler? createSampler();
+  WebGLSampler? createSampler();
   void deleteSampler(WebGLSampler? sampler);
   [WebGLHandlesContextLoss] GLboolean isSampler(WebGLSampler? sampler);
   void bindSampler(GLuint unit, WebGLSampler? sampler);
   void samplerParameteri(WebGLSampler sampler, GLenum pname, GLint param);
   void samplerParameterf(WebGLSampler sampler, GLenum pname, GLfloat param);
-  any getSamplerParameter(WebGLSampler sampler, GLenum pname);*/
+  any getSamplerParameter(WebGLSampler sampler, GLenum pname);
 
   /* Sync objects */
   WebGLSync? fenceSync(GLenum condition, GLbitfield flags);

components/script/dom/webidls/WebGLSampler.webidl

@@ -0,0 +1,11 @@
+/* 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 https://mozilla.org/MPL/2.0/. */
+//
+// WebGL IDL definitions scraped from the Khronos specification:
+// https://www.khronos.org/registry/webgl/specs/latest/1.0/#5.8
+//
+
+[Exposed=Window, Pref="dom.webgl2.enabled"]
+interface WebGLSampler : WebGLObject {
+};