I recently upgrade my Samsung Galaxy Tab 7″ (P1000) to Cyanogenmod 11.2 to attempt to fix a Bluetooth problem I’m having (which is a different matter entirely), but noticed that Whatsapp was not syncing contacts with my phone contacts at all. As a matter of fact, I wasn’t even able to add new contacts to Whatsapp or start chats with people not in my history of chats.
After much searching, I finally decided to leave it for a later time. Then one day, while looking for reasons why Waze wasn’t performing certain actions properly either, I noticed the setting (under settings | apps) “Enable Privacy Guard”. This led me to further investigate this feature.
Under settings | privacy | Privacy Guard, a list of all apps is shown and each’s guard may be enable or disabled. Lo and behold, when I disabled it for Whatsapp, suddenly the contact sync worked and my contacts where shown in Whatsapp.
I would have liked some notification by Android that Privacy Guard is on when an app attempts something that is blocked by privacy guard. Maybe it’s just not ready in CM 11.2 yet?
Anyway, if you have this problem with Whatsapp or other apps, investigate this option and maybe you find that it solves the problem like it did for me.