Auto merge of #20877 - servo:jdm-patch-6, r=emilio

Be less judgemental when tearing down WebGL rendering contexts

r? nox

- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes do not require tests because it relies on the webgl thread behaving badly.

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components/script/dom/webglrenderingcontext.rs

@@ -1193,7 +1193,7 @@ impl WebGLRenderingContext {
 
 impl Drop for WebGLRenderingContext {
     fn drop(&mut self) {
-        self.webgl_sender.send_remove().unwrap();
+        let _ = self.webgl_sender.send_remove();
     }
 }