Please describe the problem:
When inserting images inline into an html mail, if the image file-uri contains escaped characters, the files will not be included in the multipart mail. The image tag will point to the file-uri which the recipient cannot access.

Steps to reproduce:
1. Compose an e-mail in html format.
2. Drag-and-drop an image with a filename containing space into the e-mail body.
3. Send the mail.


Actual results:
The image file will not be attached and the img tag will have the file-uri as source.

Expected results:
The image file should be included in the e-mail and the img tag should have a cid source.

Does this happen every time?
Yes.

Other information:
A patch against svn trunk is attached. This fixes the problem, but someone familiar with the code should look into it in case this causes other problems.