MainFrame scrollbars should work with RFV instead of FV

third_party/WebKit/LayoutTests/paint/invalidation/window-resize-centered-inline-under-fixed-pos-expected.txt

 {
   "layers": [
     {
       "name": "LayoutView #document",
       "bounds": [600, 250],
       "contentsOpaque": true,
       "drawsContent": true,
       "paintInvalidations": [
         {
           "object": "LayoutBlockFlow (positioned) DIV class='container'",
@@ skipping 122 matching lines @@
   "layers": [
     {
       "name": "LayoutView #document",
       "bounds": [400, 600],
       "contentsOpaque": true,
       "drawsContent": true,
       "paintInvalidations": [
         {
           "object": "LayoutBlockFlow (positioned) DIV class='container'",
           "rect": [0, 0, 400, 600],
-          "reason": "full"
+          "reason": "forced by layout"

[ymalik, 2016/11/03 18:49:12]

This and other resize window tests are updated because of timing. When the
window is resized, the visual viewport first reflects this new size. Because
FV::computeScrollbarExistance works with the visual viewport's
visibleContentRect now (see RFV::visibleContentRect), it sees the updated state
before it did without this patch.

[bokan, 2016/11/03 19:59:59]

Acknowledged.

         },
         {
           "object": "LayoutView #document",
           "rect": [0, 250, 400, 350],
           "reason": "incremental"
         },
         {
           "object": "LayoutBlockFlow HTML",
           "rect": [0, 0, 400, 8],
           "reason": "forced by layout"
@@ skipping 20 matching lines @@
     {
       "object": "LayoutView #document",
       "reason": "incremental"
     },
     {
       "object": "LayoutBlockFlow HTML",
       "reason": "forced by layout"
     },
     {
       "object": "LayoutBlockFlow (positioned) DIV class='container'",
-      "reason": "full"
+      "reason": "forced by layout"
     },
     {
       "object": "LayoutBlockFlow DIV class='parent'",
       "reason": "forced by layout"
     },
     {
       "object": "RootInlineBox",
       "reason": "forced by layout"
     },
     {
       "object": "LayoutBlockFlow (relative positioned) DIV class='child'",
       "reason": "forced by layout"
     }
   ]
 }
 {
   "layers": [
     {
       "name": "LayoutView #document",
       "bounds": [800, 600],
       "contentsOpaque": true,
       "drawsContent": true,
       "paintInvalidations": [
         {
           "object": "LayoutBlockFlow (positioned) DIV class='container'",
           "rect": [0, 0, 800, 600],
-          "reason": "full"
+          "reason": "forced by layout"
         },
         {
           "object": "LayoutBlockFlow HTML",
           "rect": [0, 0, 800, 8],
           "reason": "forced by layout"
         },
         {
           "object": "LayoutView #document",
           "rect": [400, 0, 400, 600],
           "reason": "incremental"
@@ skipping 15 matching lines @@
     {
       "object": "LayoutView #document",
       "reason": "incremental"
     },
     {
       "object": "LayoutBlockFlow HTML",
       "reason": "forced by layout"
     },
     {
       "object": "LayoutBlockFlow (positioned) DIV class='container'",
-      "reason": "full"
+      "reason": "forced by layout"
     },
     {
       "object": "LayoutBlockFlow DIV class='parent'",
       "reason": "forced by layout"
     },
     {
       "object": "RootInlineBox",
       "reason": "forced by layout"
     },
     {
       "object": "LayoutBlockFlow (relative positioned) DIV class='child'",
       "reason": "forced by layout"
     }
   ]
 }