[INTERNAL] sap.m.Panel: design time metadata aggregation domRef declaration fix
[INTERNAL] sap.m.Panel: design time metadata aggregation domRef declaration fix

In case of several composed Panels imprecise selectors fetchs all the aggregation
DOM Nodes of all internal Panels with following consequences.

Change-Id: I64687a469e13315252311882ae34011c395fb95d
BCP: 1870376859

SAP/openui5,SAP/openui5,SAP/openui5,SAP/openui5