Auto merge of #22798 - jdm:webgl-trace, r=nox

Report all messages processed by the webgl thread.

This might be useful for figuring out what a WebGL-based page is doing when it's not behaving correctly.

---
- [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 they are debug-logging changes only.

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components/script/dom/webglrenderingcontext.rs

@@ -708,7 +708,7 @@ impl WebGLRenderingContext {
             alpha_treatment,
             y_axis_treatment,
             pixel_format: pixels.pixel_format,
-            data: pixels.data,
+            data: pixels.data.into(),
         });
 
         if let Some(fb) = self.bound_framebuffer.get() {
@@ -783,7 +783,7 @@ impl WebGLRenderingContext {
             alpha_treatment,
             y_axis_treatment,
             pixel_format: pixels.pixel_format,
-            data: pixels.data,
+            data: pixels.data.into(),
         });
     }