Use Shadow DOM to display fallback content for images

LayoutTests/fast/forms/state-restore-to-non-edited-controls.html

Index: LayoutTests/fast/forms/state-restore-to-non-edited-controls.html
diff --git a/LayoutTests/fast/forms/state-restore-to-non-edited-controls.html b/LayoutTests/fast/forms/state-restore-to-non-edited-controls.html
index 6aebc5837d6f21bfeea459b1a9b51ee9a9dd4957..a2f3867bb0038d2bc491d86b559d6887a3d3dcad 100644
--- a/LayoutTests/fast/forms/state-restore-to-non-edited-controls.html
+++ b/LayoutTests/fast/forms/state-restore-to-non-edited-controls.html
@@ -40,7 +40,7 @@ function runTest()
     
         document.getElementById('text1').value = 'edit';
         // Submit form in a timeout to make sure that we create a new back/forward list item.            
-        setTimeout(function() {document.getElementById('form1').submit();}, 0);
+        setTimeout(function() {document.getElementById('form1').submit();}, 100);
     } else {
         // Second visit.
         makeForm(parent, '2', '2', '2', '2', '2', '2', '2', '2', '2');