Sync CSS interfaces with the specs

Source/core/css/CSSSupportsRule.idl

Index: Source/core/css/CSSSupportsRule.idl
diff --git a/Source/core/css/CSSSupportsRule.idl b/Source/core/css/CSSSupportsRule.idl
index 3329c9e0a84c632e2ff62f2804ca9481ea6099c5..d06a77968f98de5710c196f6b32a70ffdc84219a 100644
--- a/Source/core/css/CSSSupportsRule.idl
+++ b/Source/core/css/CSSSupportsRule.idl
@@ -26,10 +26,15 @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
+// http://dev.w3.org/csswg/css-conditional/#the-csssupportsrule-interface
+
+// TODO(philipj): CSSSupportsRule should inherit from CSSConditionRule and
+// inherit all members.
 interface CSSSupportsRule : CSSRule {
-    readonly attribute CSSRuleList cssRules;
+    // http://dev.w3.org/csswg/css-conditional/#the-cssconditionrule-interface
     readonly attribute DOMString conditionText;
-
+    // http://dev.w3.org/csswg/cssom/#the-cssgroupingrule-interface
+    [SameObject] readonly attribute CSSRuleList cssRules;
     [RaisesException] unsigned long insertRule(DOMString rule, unsigned long index);
     [RaisesException] void deleteRule(unsigned long index);
 };