[BZ 1031730] - Dashboard graph group does not retain group configuration - SingleResourceGroupSelector component now pre-selects the group stored in user prefs

Cherry-Pick master: 7c78a3b78dadcb401ea279f6f1aa47310996855c
[BZ 1031730] - Dashboard graph group does not retain group configuration - removing one unnecessary call of doPostPopulateAvailableGrid(), adding i18n for a message from AbstractSelector, reducing visibility from public to protected

Cherry-Pick Master 139f3785dd19c3e2070795af6b21fc289de97edc