script: Remove explicit reflow for web font loads (#32455)

Instead of using an explicit reflow when a web font laods, queue a
pending reflow. This should be able to eliminate multiple reflows some
situations. A followup should ensure that only nodes that have pending
fonts loading are reflows, but this change is the first step.

components/script/dom/window.rs

@@ -182,7 +182,6 @@ pub enum ReflowReason {
     StylesheetLoaded,
     Timer,
     Viewport,
-    WebFontLoaded,
     WindowResize,
     WorkletLoaded,
 }