Put SVGResourceContainer subtypes into their own property trees.

third_party/WebKit/LayoutTests/paint/invalidation/svg/use-setAttribute-crash-expected.txt

 {
   "layers": [
     {
       "name": "LayoutView #document",
       "bounds": [800, 600],
       "contentsOpaque": true,
       "drawsContent": true,
       "paintInvalidations": [
         {
           "object": "LayoutBlockFlow body",
           "rect": [8, 8, 784, 204],
           "reason": "forced by layout"
         },
         {
           "object": "LayoutSVGEllipse svg:circle id='circle'",
           "rect": [32, 32, 52, 52],
           "reason": "layoutObject insertion"
         },
         {
           "object": "LayoutSVGEllipse svg:circle id='circle'",
-          "rect": [7, 7, 27, 27],
-          "reason": "subtree"
-        },
-        {
-          "object": "LayoutSVGEllipse svg:circle id='circle'",
           "rect": [52, 52, 12, 12],
           "reason": "layoutObject removal"
         },
         {
           "object": "LayoutSVGViewportContainer svg id='symbol'",
           "rect": [53, 53, 10, 10],
           "reason": "layoutObject removal"
         }
       ]
     }
@@ skipping 31 matching lines @@
       "object": "LayoutSVGViewportContainer svg id='symbol'",
       "reason": "layoutObject insertion"
     },
     {
       "object": "LayoutSVGEllipse svg:circle id='circle'",
       "reason": "layoutObject insertion"
     }
   ]
 }