Remove the HasOwnBackingButPaintsIntoAncestor compositing state.

LayoutTests/platform/win/compositing/geometry/preserve-3d-switching-expected.txt

 The green box appear angled out from the yellow box and embedded in it.
 
 transform: translateZ(-100px) rotateY(45deg);
 {
   "bounds": [800, 600],
   "children": [
     {
       "bounds": [800, 600],
       "contentsOpaque": true,
       "drawsContent": true,
       "children": [
         {
           "position": [108, 72],
           "bounds": [304, 304],
+          "drawsContent": true,
           "children": [
             {
               "bounds": [304, 304],
               "shouldFlattenTransform": false,
               "transform": [
                 [1, 0, 0, 0],
                 [0, 1, 0, 0],
                 [0, 0, 1, -0.002],
                 [0, 0, 0, 1]
               ],
@@ skipping 33 matching lines @@
                 }
               ]
             }
           ]
         }
       ]
     }
   ]
 }