WASHINGTON — Okello Chatrie’s cellphone gave him away. Chatrie made off with $195,000 from the bank he robbed in suburban Richmond, Virginia, and eluded the police until they turned to a powerful technological tool that erected a virtual fence and allowed them collect the location history of cellphone users near the crime scene. The geofence warrant police served on Google found that Chatrie’s cellphone was among a handful of devices in the vicinity of the bank around the time it was robbed.