Avoid requiring a recalc to update compositing state for iframes

LayoutTests/platform/mac/fast/frames/001-expected.txt

Index: LayoutTests/platform/mac/fast/frames/001-expected.txt
diff --git a/LayoutTests/fast/frames/001-expected.txt b/LayoutTests/platform/mac/fast/frames/001-expected.txt
similarity index 80%
copy from LayoutTests/fast/frames/001-expected.txt
copy to LayoutTests/platform/mac/fast/frames/001-expected.txt
index 83247f770a2e06198e5c9e987796de05b7b29496..68e75d3def8de98aee4d71bc1f4a655d0180810e 100644
--- a/LayoutTests/fast/frames/001-expected.txt
+++ b/LayoutTests/platform/mac/fast/frames/001-expected.txt
@@ -6,12 +6,6 @@ layer at (0,0) size 800x600
       RenderText {#text} at (0,0) size 522x18
         text run at (0,0) width 522: "The three red squares below should all look the same and be filled only with black."
       RenderBR {BR} at (522,14) size 0x0
-      RenderPartObject {IFRAME} at (0,18) size 170x170 [border: (10px solid #FF0000)]
-        layer at (0,0) size 100x100
-          RenderView at (0,0) size 100x100
-        layer at (0,0) size 100x100
-          RenderBlock {HTML} at (0,0) size 100x100
-            RenderBody {BODY} at (8,8) size 84x84
       RenderText {#text} at (170,174) size 4x18
         text run at (170,174) width 4: " "
       RenderEmbeddedObject {OBJECT} at (174,18) size 170x170 [border: (10px solid #FF0000)]
@@ -29,3 +23,10 @@ layer at (0,0) size 800x600
           RenderBlock {HTML} at (0,0) size 100x100
             RenderBody {BODY} at (8,8) size 84x84
       RenderText {#text} at (0,0) size 0x0
+layer at (8,26) size 170x170
+  RenderPartObject {IFRAME} at (0,18) size 170x170 [border: (10px solid #FF0000)]
+    layer at (0,0) size 100x100
+      RenderView at (0,0) size 100x100
+    layer at (0,0) size 100x100
+      RenderBlock {HTML} at (0,0) size 100x100
+        RenderBody {BODY} at (8,8) size 84x84