Revert "compositor: Unify the cross process and in-process API (#36443)" (#36533)

This reverts commit 4c55104b36.

This commit introduced an issue where messages from script to the
compositor no longer woke up the embedder. There is a larger issue
here, but this change exacerbated it.

Fixes #36528.

Signed-off-by: Martin Robinson <mrobinson@igalia.com>

components/script/dom/window.rs

@@ -1899,7 +1899,10 @@ impl Window {
         let (sender, receiver) =
             ProfiledIpc::channel::<DeviceIndependentIntRect>(timer_profile_chan).unwrap();
         let _ = self.compositor_api.sender().send(
-            compositing_traits::CompositorMsg::GetClientWindowRect(self.webview_id(), sender),
+            compositing_traits::CrossProcessCompositorMessage::GetClientWindowRect(
+                self.webview_id(),
+                sender,
+            ),
         );
         let rect = receiver.recv().unwrap_or_default();
         (