Auto merge of #25903 - mmatyas:webgl_fns_framebuf_render_validation_fix, r=jdm

Improved the WebGL2 framebuffer render validation

It seems `MissingColorAttachment` should be returned only when all of the color attachments are missing.

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cc @jdm @zakorgy

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components/script/dom/webglframebuffer.rs

@@ -468,7 +468,7 @@ impl WebGLFramebuffer {
             return CompleteForRendering::Complete;
         }
 
-        if self.colors.iter().any(|att| att.borrow().is_none()) {
+        if self.colors.iter().all(|att| att.borrow().is_none()) {
             return CompleteForRendering::MissingColorAttachment;
         }