Permission error on survey update
The user who answer the survey may not have delete permission for the user_input_line
In a survey, for a survey user (!= manager),
When browsing previous pages of anwsers,
the user wasn't allowed to change his answers
regarding simple choice, multiple choices and matrix
questions, as this kind of answers changes leaded to an
unlink operation, not allowed for survey users.
Closes#2901
4c610a31b9