When email has an invalid address the mail handlers can throw a MessageException

A user in support had their JIRA instance receiving an email with an address that java mail feels is invalid.

This generates a MessageException in the handleMessage method of our email handlers.

javax.mail.internet.AddressException: Illegal whitespace in address in string ``jira_gmitbrazil (APPLICATION)''
at javax.mail.internet.InternetAddress.checkAddress(InternetAddress.java:900)
at javax.mail.internet.InternetAddress.parse(InternetAddress.java:793)
at javax.mail.internet.InternetAddress.parseHeader(InternetAddress.java:554)
at javax.mail.internet.MimeMessage.getAddressHeader(MimeMessage.java:658)
at javax.mail.internet.MimeMessage.getRecipients(MimeMessage.java:483)
at javax.mail.Message.getAllRecipients(Message.java:272)
at javax.mail.internet.MimeMessage.getAllRecipients(MimeMessage.java:498)
at com.atlassian.mail.MailUtils.hasRecipient(MailUtils.java:254)
at com.atlassian.jira.service.util.handler.AbstractMessageHandler.canHandleMessage(AbstractMessageHandler.java:206)
at com.atlassian.jira.service.util.handler.AbstractCommentHandler.handleMessage(AbstractCommentHandler.java:55)
at com.atlassian.jira.service.services.mail.MailFetcherService.run(MailFetcherService.java:190)
at com.atlassian.jira.service.JiraServiceContainerImpl.run(JiraServiceContainerImpl.java:67)
at com.atlassian.jira.service.ServiceRunner.execute(ServiceRunner.java:61)
at org.quartz.core.JobRunShell.run(JobRunShell.java:191)
at org.quartz.simpl.SimpleThreadPool$WorkerThread.run(SimpleThreadPool.java:516)

The exception propagates up to the MailFetcherService where all we do is log the exception and leave the mail behind.

In this case we really want to forward the message on to the forward address (if specified).

The problem is that the canHandleMessage call is not inside the try/catch that looks for a message exception.

See JSP-32493 for more details.