Add method zcl_srtti_typedescr=>create_by_data_ref

[sandraros]

Currently, only zcl_srtti_typedescr=>create_by_data_object exists.

Request to also have zcl_srtti_typedescr=>create_by_data_ref, it's very useful because S-RTTI is used with dynamic data, so data references are often used.

  class-methods CREATE_BY_DATA_REF
    importing
      !DATA_ref type REF TO DATA
    returning
      value(SRTTI) type ref to ZCL_AUTUW_SRTTI_TYPEDESCR .

  METHOD CREATE_BY_DATA_REF.

    srtti = create_by_rtti( cl_abap_typedescr=>describe_by_data_ref( data_ref ) ).

  ENDMETHOD.