[INTERNAL] sap.m.Combobox: make test discoverable
[INTERNAL] sap.m.Combobox: make test discoverable

If a sap.m.Dialog is used (mobile devicess) for combobox the destroy has to be shifted after the dialog was closed

Change-Id: I43bddefc038a2113b8d5c06aa42aa128e82893a1

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