Blank item shows in app permission list after app is uninstalled

[TarotChen]

$ system-image-cli -i
current build number: 290
device name: krillin
channel: ubuntu-touch/rc-proposed/bq-aquaris.en
last update: 2016-03-23 07:08:55
version version: 290
version ubuntu: 20160323
version device: 20160108-efc96d8
version custom: 20160111-926-36--vivid

Steps:
1.Download OSMtouch from store
2.Launch the app and accept the trust prompt
3.Go to System Settings->Security&Privacy->App permissions->Location
>OSMtouch is listed and switch is on
4.Go to app scope and uninstall OSMtouch
5.Go to System Settings->Security&Privacy->App permissions->Location and check again

Actual result:
Blank item shows with switch on

Expected result:
OSMtouch should be removed from permission list as well