Make profiler work again (#10462)

client/src/main/java/com/vaadin/client/Profiler.java

@@ -289,7 +289,7 @@ public class Profiler {
 
         private native String getEvtGroup()
         /*-{
-            return this.EVT_GROUP;
+            return this.evtGroup;
         }-*/;
 
         private native double getMillis()