mail consumer (imap) polls continuously (not using the default polling interval)

The mail consumer (at least IMAP) would poll email continuously unless the consumer.delay is explicitly set. Below is the IMAP debug log. It should stop at A6 instead of continuing indefinitely. This does not happen with 2.14.x.

2015-07-05 20:04:02,534 [0 - imaps://imap.gmail.com:993] DEBUG MailConsumer - Connecting to MailStore: imaps://imap.gmail.com:993 (SSL enabled), folder=INBOX
DEBUG: getProvider() returning javax.mail.Provider[STORE,imaps,com.sun.mail.imap.IMAPSSLStore,Oracle]
DEBUG IMAPS: mail.imap.fetchsize: 16384
DEBUG IMAPS: mail.imap.ignorebodystructuresize: false
DEBUG IMAPS: mail.imap.statuscachetimeout: 1000
DEBUG IMAPS: mail.imap.appendbuffersize: -1
DEBUG IMAPS: mail.imap.minidletime: 10
DEBUG IMAPS: trying to connect to host "imap.gmail.com", port 993, isSSL true

• OK Gimap ready for requests from 76.108.169.41 k7mb499616512ywc
  A0 CAPABILITY
• CAPABILITY IMAP4rev1 UNSELECT IDLE NAMESPACE QUOTA ID XLIST CHILDREN X-GM-EXT-1 XYZZY SASL-IR AUTH=XOAUTH2 AUTH=PLAIN AUTH=PLAIN-CLIENTTOKEN AUTH=XOAUTH
  A0 OK Thats all she wrote! k7mb499616512ywc
  DEBUG IMAPS: AUTH: XOAUTH2
  DEBUG IMAPS: AUTH: PLAIN
  DEBUG IMAPS: AUTH: PLAIN-CLIENTTOKEN
  DEBUG IMAPS: AUTH: XOAUTH
  DEBUG IMAPS: protocolConnect login, host=imap.gmail.com, user=test@e-bonding.com, password=<non-null>
  DEBUG IMAPS: AUTHENTICATE PLAIN command trace suppressed
  DEBUG IMAPS: AUTHENTICATE PLAIN command result: A1 OK test@e-bonding.com authenticated (Success)
  A2 CAPABILITY
• CAPABILITY IMAP4rev1 UNSELECT IDLE NAMESPACE QUOTA ID XLIST CHILDREN X-GM-EXT-1 UIDPLUS COMPRESS=DEFLATE ENABLE MOVE CONDSTORE ESEARCH UTF8=ACCEPT
  A2 OK Success
  2015-07-05 20:04:03,120 [0 - imaps://imap.gmail.com:993] DEBUG MailConsumer - Getting folder INBOX
  A3 LIST "" INBOX
• LIST (\HasNoChildren) "/" "INBOX"
  A3 OK Success
  2015-07-05 20:04:03,162 [0 - imaps://imap.gmail.com:993] DEBUG MailConsumer - Polling mailbox folder: imaps://imap.gmail.com:993 (SSL enabled), folder=INBOX
  DEBUG IMAPS: connection available – size: 1
  A4 SELECT INBOX
• FLAGS (\Answered \Flagged \Draft \Deleted \Seen $NotPhishing $Phishing)
• OK [PERMANENTFLAGS (\Answered \Flagged \Draft \Deleted \Seen $NotPhishing $Phishing \*)] Flags permitted.
• OK [UIDVALIDITY 1] UIDs valid.
• 53 EXISTS
• 0 RECENT
• OK [UIDNEXT 294] Predicted next UID.
• OK [HIGHESTMODSEQ 85418]
  A4 OK [READ-WRITE] INBOX selected. (Success)
  A5 SEARCH UNSEEN ALL
• SEARCH
  A5 OK SEARCH completed (Success)
  2015-07-05 20:04:03,272 [0 - imaps://imap.gmail.com:993] DEBUG MailConsumer - Fetching 0 messages. Total 0 messages.
  2015-07-05 20:04:03,272 [0 - imaps://imap.gmail.com:993] DEBUG MailConsumer - Close mailbox folder INBOX from imaps://imap.gmail.com:993 (SSL enabled), folder=INBOX
  A6 CLOSE
  A6 OK Returned to authenticated state. (Success)
  DEBUG IMAPS: added an Authenticated connection – size: 1
  DEBUG IMAPS: IMAPProtocol noop
  A7 NOOP
  A7 OK Success
  2015-07-05 20:04:03,880 [0 - imaps://imap.gmail.com:993] DEBUG MailConsumer - Polling mailbox folder: imaps://imap.gmail.com:993 (SSL enabled), folder=INBOX
  DEBUG IMAPS: connection available – size: 1
  A8 SELECT INBOX
• FLAGS (\Answered \Flagged \Draft \Deleted \Seen $NotPhishing $Phishing)
• OK [PERMANENTFLAGS (\Answered \Flagged \Draft \Deleted \Seen $NotPhishing $Phishing \*)] Flags permitted.
• OK [UIDVALIDITY 1] UIDs valid.
• 53 EXISTS
• 0 RECENT
• OK [UIDNEXT 294] Predicted next UID.
• OK [HIGHESTMODSEQ 85418]
  A8 OK [READ-WRITE] INBOX selected. (Success)
  A9 SEARCH UNSEEN ALL
• SEARCH
  A9 OK SEARCH completed (Success)
  2015-07-05 20:04:04,003 [0 - imaps://imap.gmail.com:993] DEBUG MailConsumer - Fetching 0 messages. Total 0 messages.
  2015-07-05 20:04:04,004 [0 - imaps://imap.gmail.com:993] DEBUG MailConsumer - Close mailbox folder INBOX from imaps://imap.gmail.com:993 (SSL enabled), folder=INBOX
  A10 CLOSE
  A10 OK Returned to authenticated state. (Success)
  DEBUG IMAPS: added an Authenticated connection – size: 1
  DEBUG IMAPS: IMAPProtocol noop
  A11 NOOP
  A11 OK Success
  2015-07-05 20:04:04,572 [0 - imaps://imap.gmail.com:993] DEBUG MailConsumer - Polling mailbox folder: imaps://imap.gmail.com:993 (SSL enabled), folder=INBOX
  DEBUG IMAPS: connection available – size: 1
  A12 SELECT INBOX
• FLAGS (\Answered \Flagged \Draft \Deleted \Seen $NotPhishing $Phishing)
• OK [PERMANENTFLAGS (\Answered \Flagged \Draft \Deleted \Seen $NotPhishing $Phishing \*)] Flags permitted.
• OK [UIDVALIDITY 1] UIDs valid.
• 53 EXISTS
• 0 RECENT
• OK [UIDNEXT 294] Predicted next UID.
• OK [HIGHESTMODSEQ 85418]
  A12 OK [READ-WRITE] INBOX selected. (Success)
  A13 SEARCH UNSEEN ALL
• SEARCH
  A13 OK SEARCH completed (Success)
  2015-07-05 20:04:04,665 [0 - imaps://imap.gmail.com:993] DEBUG MailConsumer - Fetching 0 messages. Total 0 messages.
  2015-07-05 20:04:04,665 [0 - imaps://imap.gmail.com:993] DEBUG MailConsumer - Close mailbox folder INBOX from imaps://imap.gmail.com:993 (SSL enabled), folder=INBOX
  A14 CLOSE
  A14 OK Returned to authenticated state. (Success)
  DEBUG IMAPS: added an Authenticated connection – size: 1
  DEBUG IMAPS: IMAPProtocol noop
  A15 NOOP
  A15 OK Success
  2015-07-05 20:04:05,232 [0 - imaps://imap.gmail.com:993] DEBUG MailConsumer - Polling mailbox folder: imaps://imap.gmail.com:993 (SSL enabled), folder=INBOX
  DEBUG IMAPS: connection available – size: 1
  A16 SELECT INBOX
• FLAGS (\Answered \Flagged \Draft \Deleted \Seen $NotPhishing $Phishing)
• OK [PERMANENTFLAGS (\Answered \Flagged \Draft \Deleted \Seen $NotPhishing $Phishing \*)] Flags permitted.
• OK [UIDVALIDITY 1] UIDs valid.
• 53 EXISTS
• 0 RECENT
• OK [UIDNEXT 294] Predicted next UID.
• OK [HIGHESTMODSEQ 85418]
  A16 OK [READ-WRITE] INBOX selected. (Success)
  A17 SEARCH UNSEEN ALL
• SEARCH
  A17 OK SEARCH completed (Success)
  2015-07-05 20:04:05,357 [0 - imaps://imap.gmail.com:993] DEBUG MailConsumer - Fetching 0 messages. Total 0 messages.
  2015-07-05 20:04:05,358 [0 - imaps://imap.gmail.com:993] DEBUG MailConsumer - Close mailbox folder INBOX from imaps://imap.gmail.com:993 (SSL enabled), folder=INBOX
  A18 CLOSE
  A18 OK Returned to authenticated state. (Success)
  DEBUG IMAPS: added an Authenticated connection – size: 1