[INTERNAL][FIX] sap.f.DynamicPage: private method _getScrollPosition corrected
[INTERNAL][FIX] sap.f.DynamicPage: private method _getScrollPosition corrected

BCP: 1780137503

Change-Id: I166f45725095dffe12b175cc99fbdba81dde0ea4

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