adding password protection check to getShareByToken()
in case no share is found for the given token we can return right away
fixing comment + adding unit test for checkPasswordProtectedShare
Merge branch 'master' into fixing-gallery-password-protected-access-master
Merge branch 'master' into fixing-gallery-password-protected-access-master
Merge pull request #6856 from owncloud/fixing-gallery-password-protected-access-master

adding password protection check to getShareByToken()