Sky: Change iframe positioning to use absoluteContentBox for the View's

sky/tests/lowlevel/iframe-expected.txt

Index: sky/tests/lowlevel/iframe-expected.txt
diff --git a/sky/tests/lowlevel/iframe-expected.txt b/sky/tests/lowlevel/iframe-expected.txt
index 003120ff673f08df284392caa04f5056ea1bdeff..6495ab1f1fc313573a599354056265d3f5e05543 100644
--- a/sky/tests/lowlevel/iframe-expected.txt
+++ b/sky/tests/lowlevel/iframe-expected.txt
@@ -1,14 +1,26 @@
 layer at (0,0) size 800x600
   RenderView {#document} at (0,0) size 800x600
-layer at (0,0) size 800x188
-  RenderBlock {sky} at (0,0) size 800x188
-    RenderBlock {div} at (0,0) size 800x188
+layer at (0,0) size 800x506
+  RenderBlock {sky} at (0,0) size 800x506
+    RenderBlock {div} at (0,0) size 800x228
       RenderBlock (anonymous) at (0,0) size 800x19
         RenderText {#text} at (0,0) size 76x19
           text run at (0,0) width 76: "This is an"
-      RenderBlock (anonymous) at (0,169) size 800x19
+      RenderBlock (anonymous) at (0,209) size 800x19
         RenderText {#text} at (0,0) size 72x19
           text run at (0,0) width 72: "element."
-layer at (250,19) size 300x150
-  RenderReplaced {iframe} at (250,19) size 300x150
+    RenderBlock {div} at (0,228) size 800x200
+      RenderText {#text} at (0,0) size 99x19
+        text run at (0,0) width 99: "Placeholder."
+    RenderBlock {div} at (0,428) size 800x78
+      RenderBlock (anonymous) at (0,0) size 800x19
+        RenderText {#text} at (0,0) size 218x19
+          text run at (0,0) width 218: "Small iframe should render"
+      RenderBlock (anonymous) at (0,59) size 800x19
+        RenderText {#text} at (0,0) size 76x19
+          text run at (0,0) width 76: "correctly."
+layer at (230,19) size 340x190
+  RenderReplaced {iframe} at (230,19) size 340x190 [border: (20px solid #000000)]
+layer at (250,447) size 300x40
+  RenderReplaced {iframe} at (250,19) size 300x40