Simplify incremental paint invalidation

third_party/WebKit/LayoutTests/platform/linux/paint/invalidation/table-collapsed-border-expected.txt

 {
   "layers": [
     {
       "name": "LayoutView #document",
       "bounds": [800, 600],
       "contentsOpaque": true,
       "drawsContent": true,
       "paintInvalidations": [
         {
           "object": "LayoutTable TABLE",
@@ skipping 89 matching lines @@
           "object": "LayoutText #text",
           "rect": [23, 225, 32, 19],
           "reason": "layoutObject removal"
         },
         {
           "object": "LayoutTable TABLE",
           "rect": [74, 286, 29, 82],
           "reason": "incremental"
         },
         {
-          "object": "LayoutTable TABLE",
-          "rect": [78, 286, 25, 82],
-          "reason": "incremental"
-        },
-        {
           "object": "LayoutTableCell TD",
           "rect": [8, 224, 14, 22],
           "reason": "forced by layout"
         },
         {
           "object": "LayoutTableCell TD",
           "rect": [8, 132, 14, 22],
           "reason": "forced by layout"
         },
         {
@@ skipping 182 matching lines @@
       "object": "LayoutText #text",
       "reason": "forced by layout"
     },
     {
       "object": "InlineTextBox 'sit amet'",
       "reason": "forced by layout"
     }
   ]
 }