Don't always fully repaint on viewport resize

LayoutTests/fast/repaint/window-resize-no-layout-change2-expected.txt

Index: LayoutTests/fast/repaint/window-resize-no-layout-change2-expected.txt
diff --git a/LayoutTests/fast/repaint/window-resize-no-layout-change2-expected.txt b/LayoutTests/fast/repaint/window-resize-no-layout-change2-expected.txt
index 085b1b2ccebe0204770f156522297b8b0b21065c..0876a2b36f54e702ea60d82c7e7e1cf4c30a0af9 100644
--- a/LayoutTests/fast/repaint/window-resize-no-layout-change2-expected.txt
+++ b/LayoutTests/fast/repaint/window-resize-no-layout-change2-expected.txt
@@ -6,9 +6,7 @@
       (contentsOpaque 1)
       (drawsContent 1)
       (repaint rects
-        (rect 0.00 0.00 2008.00 2008.00)
-        (rect 0.00 0.00 200.00 300.00)
-        (rect 0.00 0.00 200.00 200.00)
+        (rect 0.00 200.00 200.00 100.00)
       )
     )
   )
@@ -21,9 +19,8 @@
       (contentsOpaque 1)
       (drawsContent 1)
       (repaint rects
+        (rect 200.00 0.00 100.00 300.00)
         (rect 0.00 0.00 2008.00 2008.00)
-        (rect 0.00 0.00 300.00 300.00)
-        (rect 0.00 0.00 200.00 300.00)
       )
     )
   )
@@ -36,9 +33,7 @@
       (contentsOpaque 1)
       (drawsContent 1)
       (repaint rects
-        (rect 0.00 0.00 2008.00 2008.00)
-        (rect 0.00 0.00 300.00 300.00)
-        (rect 0.00 0.00 300.00 250.00)
+        (rect 0.00 250.00 300.00 50.00)
       )
     )
   )
@@ -51,9 +46,8 @@
       (contentsOpaque 1)
       (drawsContent 1)
       (repaint rects
+        (rect 250.00 0.00 50.00 250.00)
         (rect 0.00 0.00 2008.00 2008.00)
-        (rect 0.00 0.00 300.00 250.00)
-        (rect 0.00 0.00 250.00 250.00)
       )
     )
   )