Empty file type for MS Office documents dropped as folder content

[x68507]

When dropping an entire folder structure onto the DropZone, the MIME type is lost for Microsoft Office file types, replacing what should be an application specific filetype (such as application/vnd.ms-excel for Excel2003) with an arbitrary application/octet-stream. This does not occur if I open the folder and drag all the contents into the DropZone, only if I drag the actual folder itself into the DropZone.

[blueimp]

This is a bug in Chrome, which can be reproduced independently of the File Upload plugin. I've created JSFiddle here: http://jsfiddle.net/sGTkV/1/

Drag&Drop a MS Office file onto the "Result" pane and check the developer console. The first log entry (which is used for files not in folders) will report a File object with the correct file type. The second log entry (which has to be used for files in folders) will report a File object with an empty file type.

I've submitted this bug to the chromium issue tracker here: https://code.google.com/p/chromium/issues/detail?id=155455