Revert "Log broadcast action in statsd's PROCESS_START_TIME atom."

Revert "Add field broadcast_action_name to ProcessStartTime."

Revert submission 18569626-broadcast_action

Crashes the system_server when isolated processes are started!

Reason for revert: b/233958640 , b/233959324
Reverted Changes:
Ie76435e55:Add field broadcast_action_name to ProcessStartTim...
Ibf2d0c9f3:Log broadcast action in statsd's PROCESS_START_TIM...

Change-Id: Ia32b61822370b61921440993bbffecd48949c45a