After merge fixes.


sql/event_data_objects.cc:
  after merge fix. use thd->strmake instead of strmake_root
  Remove commented out code.
  Remove trailing whitespace.
sql/event_db_repository.cc:
  After merge fix.
  Before closing thread tables check whether table is actuall non-NULL.
  And always initialize it to NULL.
sql/event_queue.cc:
  Remove trailing whitespace.
sql/event_scheduler_ng.cc:
  Remove trailing whitespace.
  Tabs to spaces.
sql/events.cc:
  Remove trailing whitespace.