Bug 537065 - [NPE] NPE on SettingToControlMapperImpl

- Change to a safier method call rather than direct list access.
- add a test that was failing before fix.

Change-Id: I8cde212ec5378cdb2e3a522073f13d77d7aaa564
Signed-off-by: Remi Schnekenburger <rschnekenburger@eclipsesource.com>
2 files changed