message: Clear device_parsing_cache in context._reset_context().
  This fixes a bug where context.device("cpu:0") still resolves to a device str from an older context after resetting the context.
diff: @@ -1831,11 +1831,13 @@ def _reset_context():
  Should only be used for testing.
  """
  global _context
  + global _device_parsing_cache
  with _context_lock:
  if _context is not None:
  _context._clear_caches()
  _context = None
  _create_context()
  + _device_parsing_cache = {}
  pywrap_tfe.TFE_ClearScalarCache()
  