[INTERNAL] cleaned up EditorAPI

Removed dead methods, changed thread access.

Change-Id: Ib2175bd2ff0d65353e766a3cbbe3a6cf7da7ed4d
Reviewed-on: http://saros-build.imp.fu-berlin.de/gerrit/1827
Tested-by: Jenkins CI
Reviewed-by: Stefan Rossbach <srossbach@arcor.de>