Audit the controllers to ensure our controller guidelines/templates provide good advice

[sethkfman]

This ticket was brought up from an incident that occurred not he mobile client where a controller don't have initial state passed in the Engine which resulted in the contact list being flushed on app restart.

The outcome for this ticket will be to audit the controllers to ensure our controller guidelines/templates provide good advice on initial state.

Related issue: MetaMask/metamask-mobile#12044
Fix: MetaMask/metamask-mobile#12089

[sethkfman]

Reach out @Cal-L or @sethkfman if more context is needed.