Auto merge of #24250 - imiklos:webglsync, r=jdm

Initial implementation of WebGLSync

This patch adds initial support for [WebGLSync](https://www.khronos.org/registry/webgl/specs/latest/2.0/#3.7.14).

Note:
There is no test for the isSync, deleteSync and waitSync functions in the `conformance2/sync/sync-webgl-specific.html`.

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- [X] `./mach test-tidy` does not report any errors

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2 files changed, 13 insertions, 5 deletions

diff --git a/components/script/dom/webidls/WebGL2RenderingContext.webidl b/components/script/dom/webidls/WebGL2RenderingContext.webidl
index 13e78c72ac1..d46f3099f60 100644
--- a/components/script/dom/webidls/WebGL2RenderingContext.webidl
+++ b/components/script/dom/webidls/WebGL2RenderingContext.webidl
@@ -15,9 +15,6 @@ typedef unsigned long long GLuint64;
 // interface WebGLSampler : WebGLObject {
 // };
 
-// interface WebGLSync : WebGLObject {
-// };
-
 // interface WebGLTransformFeedback : WebGLObject {
 // };
 
@@ -542,12 +539,12 @@ interface mixin WebGL2RenderingContextBase
   any getSamplerParameter(WebGLSampler sampler, GLenum pname);*/
 
   /* Sync objects */
-  /*WebGLSync? fenceSync(GLenum condition, GLbitfield flags);
+  WebGLSync? fenceSync(GLenum condition, GLbitfield flags);
   [WebGLHandlesContextLoss] GLboolean isSync(WebGLSync? sync);
   void deleteSync(WebGLSync? sync);
   GLenum clientWaitSync(WebGLSync sync, GLbitfield flags, GLuint64 timeout);
   void waitSync(WebGLSync sync, GLbitfield flags, GLint64 timeout);
-  any getSyncParameter(WebGLSync sync, GLenum pname);*/
+  any getSyncParameter(WebGLSync sync, GLenum pname);
 
   /* Transform Feedback */
   /*WebGLTransformFeedback? createTransformFeedback();
diff --git a/components/script/dom/webidls/WebGLSync.webidl b/components/script/dom/webidls/WebGLSync.webidl
new file mode 100644
index 00000000000..3b251b8cf87
--- /dev/null
+++ b/components/script/dom/webidls/WebGLSync.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/2.0/#3.7.14
+//
+
+[Pref="dom.webgl2.enabled"]
+interface WebGLSync : WebGLObject {
+};