Rename getCancelCaption to mention Editor (#16551)

Change-Id: If0e323fcdbac519cf204d8183d2d5f9f4465a907

server/src/com/vaadin/ui/Grid.java

@@ -5069,7 +5069,7 @@ public class Grid extends AbstractComponent implements SelectionNotifier,
      * 
      * @return the current caption of the cancel button
      */
-    public String getCancelCaption() {
+    public String getEditorCancelCaption() {
         return getState(false).editorCancelCaption;
     }