Unguard Shadow DOM features.

Source/core/dom/shadow/ShadowRoot.idl

Index: Source/core/dom/shadow/ShadowRoot.idl
diff --git a/Source/core/dom/shadow/ShadowRoot.idl b/Source/core/dom/shadow/ShadowRoot.idl
index ececba5087f8628ae4d1522980dfa806b2fe7040..6e0b88c82676f68a4f4cef269791633cc19a8736 100644
--- a/Source/core/dom/shadow/ShadowRoot.idl
+++ b/Source/core/dom/shadow/ShadowRoot.idl
@@ -29,7 +29,7 @@
 ] interface ShadowRoot : DocumentFragment {
     readonly attribute Element activeElement;
     [DeprecateAs=ShadowRootApplyAuthorStyles] attribute boolean applyAuthorStyles;
-    [RuntimeEnabled=ShadowDOM, ImplementedAs=olderShadowRootForBindings] readonly attribute ShadowRoot olderShadowRoot;
+    [ImplementedAs=olderShadowRootForBindings] readonly attribute ShadowRoot olderShadowRoot;
 
     [TreatNullAs=NullString, CustomElementCallbacks, PerWorldBindings, ActivityLogging=SetterForIsolatedWorlds, RaisesException=Setter] attribute DOMString innerHTML;
 
@@ -44,6 +44,6 @@
     Element elementFromPoint([Default=Undefined] optional long x,
                              [Default=Undefined] optional long y);
 
-    [RuntimeEnabled=ShadowDOM] readonly attribute StyleSheetList styleSheets;
-    [RuntimeEnabled=ShadowDOM] readonly attribute Element host;
+    readonly attribute StyleSheetList styleSheets;
+    readonly attribute Element host;
 };