Revert "[effects/fallapart] Override scale, fade, and glide effect"

This reverts commit 1747e497e4.

Unfortunately, this patch causes fall apart effect to override sliding
popups effect, which we really don't want to do.

effects/fallapart/fallapart.cpp

@@ -163,6 +163,9 @@ void FallApartEffect::slotWindowClosed(EffectWindow* c)
         return;
     if (!c->isVisible())
         return;
+    const void* e = c->data(WindowClosedGrabRole).value<void*>();
+    if (e && e != this)
+        return;
     c->setData(WindowClosedGrabRole, QVariant::fromValue(static_cast<void*>(this)));
     windows[ c ] = 0;
     c->refWindow();