Extend the dfn of object types.

Update [SameObject] and [NewObject] to rely on it.

Fixes whatwg#71
Fixes https://www.w3.org/Bugs/Public/show_bug.cgi?id=27605

index.bs

@@ -5117,8 +5117,11 @@ are {{ArrayBuffer}},
 and the [=typed array types=].
 
 The {{object}} type,
-all [=interface types=]
-and the [=exception types=]
+all [=interface types=],
+the [=promise type=],
+the [=exception types=],
+the [=buffer source types=], and
+[=union types=] whose [=member types|members=] are [=object types=]
 are known as <dfn id="dfn-object-type" export>object types</dfn>.
 
 Every type has a <dfn id="dfn-type-name" export>type name</dfn>, which
@@ -8970,14 +8973,9 @@ The [{{NewObject}}]
 extended attribute must
 [=takes no arguments|take no arguments=].
 
-The [{{NewObject}}]
-extended attribute must not
-be used on anything other than a [=regular operation|regular=]
-or [=static operations|static=]
-[=operation=]
-whose [=return type=]
-is an [=interface type=] or
-a [=promise type=].
+The [{{NewObject}}] extended attribute must not be used on anything other than
+a [=regular operation|regular=] or [=static operations|static=] [=operation=]
+whose [=return type=] is an [=object type=].
 
 <div class="example">
 
@@ -9371,12 +9369,9 @@ The [{{SameObject}}]
 extended attribute must
 [=takes no arguments|take no arguments=].
 
-The [{{SameObject}}]
-extended attribute must not
-be used on anything other than a [=read only=]
-[=attribute=]
-whose type is an [=interface type=]
-or {{object}}.
+The [{{SameObject}}] extended attribute must not be used
+on anything other than a [=read only=] [=attribute=]
+whose type is an [=object type=].
 
 <div class="example">