Revert some changes in importer gui commit 5092

[jamoore]

r5092 will lead to new bugs.

Specifically, no call should be made to reader after an exception (see line 327). Instead, a null should be passed back, and FileQueueHandler should do something with the event.

[jmoore]

r5108 reverts to returning null. Returning a fake import container breaks directory import as well, since the detecting of isSPW() can never be completely right. This leads to an GUI exception "you've chosen both SPW and non-SPW images, please choose only one" making it useless. I'm reverting to returning null, which will prevent the path from showing up in the queue. (It was showing up in the queue as "added" anyway, rather than as "failed" as discussed)

Options:

• get rid of the restriction SPW or not SPW. This is a major workflow change
• don't worry about the return value and handle the SCANNING_FILE_EXCEPTION from all handlers (as discussed)
• using a FailedImportContainer (I'm not sure what all this entails)
• ...

[bwzloranger]

This problem is solved now by having failed candidates go directly to the failed imports queue and presenting a popup. This bypasses the normal import queue entirely.