Check below link, you need to act according to your status in Saudi Arabia.Question with regards of PCC :
I stayed in KSA until I was 19 then I moved to canada by 19.
Do I need to apply for PC from KSA ?
http://www.cic.gc.ca/english/information/security/police-cert/mid-east/saudi-arabia.asp
If you case is below one, mention clearly in LOE that “I cannot provide a police certificate for the time I spent in Saudi Arabia because certificates are only available to people who have current legal residence status."
If you are not a citizen of Saudi Arabia: AND
If you live outside of Saudi Arabia:
If you do not have current legal residence status in Saudi Arabia, you are not required to provide a Saudi Arabian police certificate. If you are asked for a police certificate from Saudi Arabia, write: “I cannot provide a police certificate for the time I spent in Saudi Arabia because certificates are only available to people who have current legal residence status.”