Reduce invalidation on children-needs-layout containers

LayoutTests/fast/repaint/invalidation-with-zero-size-object-expected.txt

 {
   "bounds": [800, 600],
   "children": [
     {
       "bounds": [800, 600],
       "contentsOpaque": true,
       "drawsContent": true,
       "repaintRects": [
-        [8, 8, 784, 200],
         [8, 8, 200, 200],
-        [8, 8, 200, 200],
-        [0, 16, 800, 200]
+        [8, 8, 200, 200]
       ]
     }
   ]
 }