Auto merge of #23135 - maharsh312:master, r=jdm

Create CanvasRect for OffscreenCanvas

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Created CanvasRect fot OffscreenCanvas and Updated Testcases

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components/script_traits/script_msg.rs

@@ -118,7 +118,7 @@ pub enum ScriptMsg {
     ChangeRunningAnimationsState(AnimationState),
     /// Requests that a new 2D canvas thread be created. (This is done in the constellation because
     /// 2D canvases may use the GPU and we don't want to give untrusted content access to the GPU.)
-    CreateCanvasPaintThread(Size2D<u32>, IpcSender<(IpcSender<CanvasMsg>, CanvasId)>),
+    CreateCanvasPaintThread(Size2D<u64>, IpcSender<(IpcSender<CanvasMsg>, CanvasId)>),
     /// Notifies the constellation that this frame has received focus.
     Focus,
     /// Requests that the constellation retrieve the current contents of the clipboard