Move FBDeviceLogCommands to -[FBFutureContext onQueue:enter:]
Move FBDeviceLogCommands to -[FBFutureContext onQueue:enter:]

Summary: We now have a generic way of doing this so we can use it and remove some of the complexity in thise class.

Reviewed By: c-ryan747

Differential Revision: D13838441

fbshipit-source-id: 4e83580101e376f2343d684d72a4125d1879900c

facebook/FBSimulatorControl,facebook/FBSimulatorControl,facebook/FBSimulatorControl,facebook/FBSimulatorControl,facebook/FBSimulatorControl