JS: Fix lack of def-node roots

Author: asgerf

javascript/ql/lib/semmle/javascript/ApiGraphs.qll

@@ -1033,6 +1033,9 @@ module API {
         rhs(_, _, rhs) and
         S::inScope(rhs) and
         nd = MkDef(rhs)
+        or
+        S::isAdditionalDefRoot(nd) and
+        nd = mkDefLate(rhs)
       }
 
       /**
@@ -1323,6 +1326,10 @@ module API {
       pragma[inline_late]
       private TApiNode mkUseLate(DataFlow::Node node) { result = MkUse(node) }
 
+      bindingset[node]
+      pragma[inline_late]
+      private TApiNode mkDefLate(DataFlow::Node node) { result = MkDef(node) }
+
       private import semmle.javascript.dataflow.TypeTracking
 
       /**