Bug 1805022 - Do round_out() surface_rect before translating in <CompositeState>::get_surface_rect. r=gw

For example, given that
  `surface_rect`: `Box2D((0.0, -1.04904175e-5), (588.99994, 0.0))`
  `surface bound`: Box2D((0.0, -512.0), (1024.0, 0.0))

Then doing round_out() after translating the surface_rect with
`-surface_bounds.min.to_vector()` results an empty rect.

We need to make sure that negative origin `surface_rect` is not collapssed.

Differential Revision: https://phabricator.services.mozilla.com/D166887

gfx/wr/webrender/src/composite.rs

@@ -592,6 +592,7 @@ impl CompositeState {
         let surface_rect = transform.local_to_surface.map_rect(&local_sub_rect);
 
         surface_rect
+            .round_out()
             .translate(-surface_bounds.min.to_vector())
             .round_out()
             .intersection(&surface_bounds.size().round().into())