Let padding change always trigger layout and full paint invalidation

third_party/WebKit/LayoutTests/paint/invalidation/box-sizing-expected.txt

 {
   "layers": [
     {
       "name": "LayoutView #document",
       "bounds": [800, 600],
       "contentsOpaque": true,
       "drawsContent": true,
       "paintInvalidations": [
         {
           "object": "LayoutBlockFlow (positioned) DIV id='target2' class='border-box'",
-          "rect": [0, 200, 440, 140],
-          "reason": "content box change"
+          "rect": [0, 280, 440, 60],
+          "reason": "incremental"
         },
         {
           "object": "LayoutBlockFlow (positioned) DIV id='target1' class='content-box'",
           "rect": [0, 80, 440, 60],
           "reason": "incremental"
         },
         {
+          "object": "LayoutBlockFlow (positioned) DIV id='target2' class='border-box'",
+          "rect": [380, 200, 60, 140],
+          "reason": "incremental"
+        },
+        {
           "object": "LayoutBlockFlow (positioned) DIV id='target1' class='content-box'",
           "rect": [380, 0, 60, 140],
           "reason": "incremental"
         }
       ]
     }
   ],
   "objectPaintInvalidations": [
     {
       "object": "LayoutBlockFlow (positioned) DIV id='target1' class='content-box'",
       "reason": "incremental"
     },
     {
       "object": "LayoutBlockFlow (positioned) DIV id='target2' class='border-box'",
-      "reason": "content box change"
+      "reason": "incremental"
     }
   ]
 }