Auto merge of #21785 - sumit0190:new_markasdirty, r=jdm

Add framebuffer check for mark_as_dirty, #21691

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Check `bound_framebuffer` in each `mark_as_dirty` call, so that we don't dirty the canvas if we don't have a bound framebuffer.

---
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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #21691  (github issue number if applicable).

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- [ ] There are tests for these changes OR
- [X] These changes do not require tests because there isn't a direct way to test it (yet).

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components/script/dom/webglrenderingcontext.rs

@@ -437,9 +437,13 @@ impl WebGLRenderingContext {
     }
 
     fn mark_as_dirty(&self) {
-        self.canvas
-            .upcast::<Node>()
-            .dirty(NodeDamage::OtherNodeDamage);
+        // If we don't have a bound framebuffer, then don't mark the canvas
+        // as dirty.
+        if self.bound_framebuffer.get().is_none() {
+            self.canvas
+                .upcast::<Node>()
+                .dirty(NodeDamage::OtherNodeDamage);
+        }
     }
 
     fn vertex_attrib(&self, indx: u32, x: f32, y: f32, z: f32, w: f32) {