Leverage the next keyword from python 2.7

This is literally what the next keyword is for.
https://www.python.org/dev/peps/pep-3114/

Change-Id: I843755910b847737b077ff2361ba3e04409db0f0

event_log.py

@@ -18,8 +18,6 @@ from __future__ import print_function
 import json
 import multiprocessing
 
-from pyversion import is_python3
-
 TASK_COMMAND = 'command'
 TASK_SYNC_NETWORK = 'sync-network'
 TASK_SYNC_LOCAL = 'sync-local'
@@ -73,7 +71,7 @@ class EventLog(object):
       A dictionary of the event added to the log.
     """
     event = {
-        'id': (kind, self._next_id.__next__() if is_python3() else self._next_id.next()),
+        'id': (kind, next(self._next_id)),
         'name': name,
         'task_name': task_name,
         'start_time': start,