Auto merge of #20317 - gootorov:webgl-getFramebufferAttachmentParameter, r=jdm

Implement WebGL getFrameBufferAttachmentParameter API

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Implementation of `getFramebufferAttachmentParameter` as in WebGL1 specification.

Part of https://github.com/servo/servo/issues/10209.

r? emilio or jdm.

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- [ ] These changes fix #__ (github issue number if applicable).

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components/script/dom/webidls/WebGLRenderingContext.webidl

@@ -589,8 +589,8 @@ interface WebGLRenderingContextBase
 
     [WebGLHandlesContextLoss] GLenum getError();
 
-    //any getFramebufferAttachmentParameter(GLenum target, GLenum attachment,
-    //                                      GLenum pname);
+    any getFramebufferAttachmentParameter(GLenum target, GLenum attachment,
+                                          GLenum pname);
     any getProgramParameter(WebGLProgram? program, GLenum pname);
     DOMString? getProgramInfoLog(WebGLProgram? program);
     //any getRenderbufferParameter(GLenum target, GLenum pname);