bugfixes

src/mxgraph/view/graph/mxGraph.ts

@@ -6071,7 +6071,7 @@ class mxGraph extends mxEventSource {
               dy: number,
               target: mxCell | null=null,
               evt: mxMouseEvent,
-              mapping: any): mxCell[] | null {
+              mapping: any={}): mxCell[] | null {
     return this.moveCells(cells, dx, dy, true, target, evt, mapping);
   }
 

src/mxgraph/view/graph/mxGraphModel.ts

@@ -2113,11 +2113,11 @@ class mxGraphModel extends mxEventSource {
    * Inner helper method for cloning cells recursively.
    */
   cloneCellImpl(cell: mxCell,
-                mapping: any,
+                mapping: any={},
                 includeChildren: boolean): mxCell {
 
     const ident = mxObjectIdentity.get(cell);
-    let clone = mapping[ident];
+    let clone = mapping ? mapping[ident] : null;
 
     if (clone == null) {
       clone = this.cellCloned(cell);