[FEATURE] MultiComboBox Keyboard Handling
[FEATURE] MultiComboBox Keyboard Handling

- Added special handling for ENTER on a selected list item.

Change-Id: I4134c6e5a2a41548be4694a13e1a0d27f4fffd71

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