Assign the correct public name value while creating schema

[sync-by-unito]

realm_core.dart

SchemaHandle _createSchema(Iterable<SchemaObject> schema) {
......
    //TODO: Assign the correct public name value

propInfo.public_name = "".toUtf8Ptr(arena);

[nirinchev]

This is a problem for @mapto as it currently generates an a SchemaProperty like:

SchemaProperty('primitive_property', RealmPropertyType.string,
          mapTo: 'primitive_property')

Note that both name and mapTo are the same. Also mapTo is not used anywhere, meaning that change notifications and queries will use the internal property name rather than the public one.