Avoid requiring a recalc to update compositing state for iframes

LayoutTests/platform/win/fast/dom/Window/open-existing-pop-up-blocking-expected.txt

Index: LayoutTests/platform/win/fast/dom/Window/open-existing-pop-up-blocking-expected.txt
diff --git a/LayoutTests/platform/win/fast/dom/Window/open-existing-pop-up-blocking-expected.txt b/LayoutTests/platform/win/fast/dom/Window/open-existing-pop-up-blocking-expected.txt
index b6bb07815adf35305ecff616fc55727bc5c74205..86cbde1d08bce117f1a785084f280e38eb648229 100644
--- a/LayoutTests/platform/win/fast/dom/Window/open-existing-pop-up-blocking-expected.txt
+++ b/LayoutTests/platform/win/fast/dom/Window/open-existing-pop-up-blocking-expected.txt
@@ -3,25 +3,27 @@ layer at (0,0) size 800x600
 layer at (0,0) size 800x600
   RenderBlock {HTML} at (0,0) size 800x600
     RenderBody {BODY} at (8,8) size 784x584
-      RenderPartObject {IFRAME} at (0,0) size 304x154 [border: (2px inset #EEEEEE)]
-        layer at (0,0) size 300x150
-          RenderView at (0,0) size 300x150
-        layer at (0,0) size 300x150
-          RenderBlock {HTML} at (0,0) size 300x150
-            RenderBody {BODY} at (8,8) size 284x134
-              RenderText {#text} at (0,0) size 275x59
-                text run at (0,0) width 263: "This frame will try to replace the contents of"
-                text run at (0,20) width 260: "the frame to the right. If the bug still occurs,"
-                text run at (0,40) width 275: "pop-up blocking will prevent it from doing so."
       RenderText {#text} at (304,139) size 4x19
         text run at (304,139) width 4: " "
-      RenderPartObject {IFRAME} at (308,0) size 304x154 [border: (2px inset #EEEEEE)]
-        layer at (0,0) size 300x150
-          RenderView at (0,0) size 300x150
-        layer at (0,0) size 300x150
-          RenderBlock {HTML} at (0,0) size 300x150
-            RenderBody {BODY} at (8,8) size 284x134
-              RenderText {#text} at (0,0) size 276x39
-                text run at (0,0) width 276: "This text successfully replaced the original text"
-                text run at (0,20) width 177: "in the frame. Test succeeded!"
       RenderText {#text} at (0,0) size 0x0
+layer at (8,8) size 304x154
+  RenderPartObject {IFRAME} at (0,0) size 304x154 [border: (2px inset #EEEEEE)]
+    layer at (0,0) size 300x150
+      RenderView at (0,0) size 300x150
+    layer at (0,0) size 300x150
+      RenderBlock {HTML} at (0,0) size 300x150
+        RenderBody {BODY} at (8,8) size 284x134
+          RenderText {#text} at (0,0) size 275x59
+            text run at (0,0) width 263: "This frame will try to replace the contents of"
+            text run at (0,20) width 260: "the frame to the right. If the bug still occurs,"
+            text run at (0,40) width 275: "pop-up blocking will prevent it from doing so."
+layer at (316,8) size 304x154
+  RenderPartObject {IFRAME} at (308,0) size 304x154 [border: (2px inset #EEEEEE)]
+    layer at (0,0) size 300x150
+      RenderView at (0,0) size 300x150
+    layer at (0,0) size 300x150
+      RenderBlock {HTML} at (0,0) size 300x150
+        RenderBody {BODY} at (8,8) size 284x134
+          RenderText {#text} at (0,0) size 276x39
+            text run at (0,0) width 276: "This text successfully replaced the original text"
+            text run at (0,20) width 177: "in the frame. Test succeeded!"