IDL: fix code generation for attributes with [PutForwards]

Source/bindings/tests/idls/TestObject.idl

Index: Source/bindings/tests/idls/TestObject.idl
diff --git a/Source/bindings/tests/idls/TestObject.idl b/Source/bindings/tests/idls/TestObject.idl
index e7b396066f39a069210b8f44ee9a7c4cdd96c746..4b8959307ac32b654437ef538d95938a628f2b05 100644
--- a/Source/bindings/tests/idls/TestObject.idl
+++ b/Source/bindings/tests/idls/TestObject.idl
@@ -198,7 +198,9 @@ interface TestObject {
     [PutForwards=href] readonly attribute TestNode location;
     [PutForwards=hrefThrows] readonly attribute TestNode locationWithException;
     [PutForwards=hrefCallWith] readonly attribute TestNode locationWithCallWith;
+    [PutForwards=hrefByteString] readonly attribute TestNode locationByteString;
     [PerWorldBindings, PutForwards=href] readonly attribute TestNode locationWithPerWorldBindings;
+    [TypeChecking=Interface, PutForwards=href] readonly attribute TestNode locationTypeCheckingInterface;
     [PutForwards=attr1] readonly attribute TestInterfaceGarbageCollected locationGarbageCollected;
     [PutForwards=attr1] readonly attribute TestInterfaceWillBeGarbageCollected locationWillBeGarbageCollected;
     [RaisesException] attribute long raisesExceptionLongAttribute;