Back Keyevent doesnt delete checked items.
UI-testcase for previous bug.
Merge branch 'master' into FEVL_KeycodeBackFix
Merge branch 'master' into FEVL_KeycodeBackFix
2.3.6 fix
Merge pull request #199 from Catrobat/FEVL_KeycodeBackFix

Successful jenkins testrun: http://catrobatgw.ist.tugraz.at:8080/job/Catroid-single-UI-test/406/