message: Remove unused DB-writer-related constants in summary_ops_v2.py
diff: @@ -54,10 +54,6 @@ from tensorflow.python.util.tf_export import tf_export
  # as a legacy API for tf.contrib.summary in TF 1.x.
  _SUMMARY_WRITER_INIT_COLLECTION_NAME = "_SUMMARY_WRITER_V2"
  -_EXPERIMENT_NAME_PATTERNS = re.compile(r"^[^\x00-\x1F<>]{0,256}$")
  -_RUN_NAME_PATTERNS = re.compile(r"^[^\x00-\x1F<>]{0,512}$")
  -_USER_NAME_PATTERNS = re.compile(r"^[a-z]([-a-z0-9]{0,29}[a-z0-9])?$", re.I)
  -
  class _SummaryState(threading.local):
  