Remove Attr child nodes (making Attr a Node, not a ContainerNode)

LayoutTests/inspector/console/console-format-expected.txt

Index: LayoutTests/inspector/console/console-format-expected.txt
diff --git a/LayoutTests/inspector/console/console-format-expected.txt b/LayoutTests/inspector/console/console-format-expected.txt
index 4c8848ab5fc11a19f5a1df3d576ab97a3ea7cda2..8b2a2044b17b76ed03a934006a5c8fc6c2f423f6 100644
--- a/LayoutTests/inspector/console/console-format-expected.txt
+++ b/LayoutTests/inspector/console/console-format-expected.txt
@@ -210,24 +210,20 @@ globals[13]
     attr=""
 console-format.html:12 
     attr="value"
-        "value"
 console-format.html:13 [attr]
     0: attr
     length: 1
     __proto__: Array[0]
 globals[14]
     attr="value"
-        "value"
 console-format.html:12 
     id="x"
-        "x"
 console-format.html:13 [id]
     0: id
     length: 1
     __proto__: Array[0]
 globals[15]
     id="x"
-        "x"
 console-format.html:12 Object {}
     length: (...)
     get length: length()