- change PatternCleanUp to not create a pattern for a String split
  if the pattern is a single-char non-meta character or is an
  escaped character that is not alpha-numeric since the String
  split() method fast-paths these without using patterns

Change-Id: I87af41904bc87f02cd8e4d4349221cb87f8cc058
Signed-off-by: Fabrice Tiercelin <fabrice.tiercelin@yahoo.fr>