After updating my Fuel Log app to take advantage of Android 6.0 (Marshmallow) run-time permissions, I noticed that app's permission page (Settings > Apps > [app name] > Permissions) contains Contacts permission that is not present AndroidManifest.xml (nor anywhere else within my app).
Google search didn't produce any results in this case, but after looking into build.gradle I noticed that I was using out of data Google Play Services version (8.3.0).
After upgrading it to 8.4.0 the issue went away.
Android Studio 1.5.1
Google Play services version 8.3.0