Don't let PaintInvalidationLocationChange shadow other reasons

third_party/WebKit/LayoutTests/platform/linux/fast/repaint/positioned-document-element-expected.txt

 {
   "bounds": [800, 600],
   "children": [
     {
       "bounds": [800, 600],
       "contentsOpaque": true,
       "drawsContent": true,
       "backgroundColor": "#008000",
       "paintInvalidations": [
         {
           "object": "LayoutView #document",
           "rect": [0, 0, 800, 600],
           "reason": "style change"
         },
         {
           "object": "LayoutBlockFlow (positioned) HTML class='changed'",
           "rect": [0, 0, 800, 52],
-          "reason": "location change"
+          "reason": "style change"
         },
         {
           "object": "LayoutBlockFlow BODY",
           "rect": [8, 16, 784, 20],
-          "reason": "location change"
+          "reason": "bounds change"
         },
         {
           "object": "LayoutBlockFlow P",
           "rect": [8, 16, 784, 20],
-          "reason": "location change"
+          "reason": "forced by layout"
         },
         {
           "object": "LayoutBlockFlow (positioned) HTML class='changed'",
           "rect": [100, 100, 418, 52],
-          "reason": "location change"
+          "reason": "style change"
         },
         {
           "object": "LayoutBlockFlow BODY",
           "rect": [108, 116, 402, 20],
-          "reason": "location change"
+          "reason": "bounds change"
         },
         {
           "object": "LayoutBlockFlow P",
           "rect": [108, 116, 402, 20],
-          "reason": "location change"
+          "reason": "forced by layout"
         },
         {
           "object": "LayoutText #text",
           "rect": [108, 116, 402, 19],
-          "reason": "location change"
+          "reason": "bounds change"
         },
         {
           "object": "LayoutText #text",
           "rect": [8, 16, 402, 19],
-          "reason": "location change"
+          "reason": "bounds change"
         },
         {
           "object": "InlineTextBox 'Tests that the entire viewport is painted with a floated html element.'",
           "reason": "full"
         },
         {
           "object": "InlineTextBox 'Tests that the entire viewport is painted with a floated html element.'",
-          "reason": "location change"
+          "reason": "bounds change"
         },
         {
           "object": "RootInlineBox",
           "reason": "full"
         },
         {
           "object": "RootInlineBox",
           "reason": "full"
         }
       ]
     }
   ]
 }