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Hi Ray.

First off, my apologies for not opening up the pull request correctly again, our internal git workflow is to PR from dev->master and I was on autopilot the last couple of days :)

I have moved the fix to (hopefully) a more appropriate place, where if there are no files present on drop the e "dropError" callback is called. I was not sure of the error code parameter as the only other place I could see this function being called was where it uses "tooManyFilesError".