[INTERNAL] sap.m.Popover: Fix when there are no pages in the NavContainer
[INTERNAL] sap.m.Popover: Fix when there are no pages in the NavContainer

Change-Id: I59e954e948d6f4e0be76887d9be68903d2e2aede

SAP/openui5,SQCLabs/openui5,SQCLabs/openui5,SAP/openui5,SAP/openui5,SAP/openui5,SQCLabs/openui5,nzamani/openui5,olirogers/openui5,cschuff/openui5,olirogers/openui5,nzamani/openui5,nzamani/openui5,cschuff/openui5,cschuff/openui5,olirogers/openui5