[WebPositive] Dropbox commands not handled correctly

[anevilyak]

While logging into DropBox and browsing it works fine, I cannot successfully download a file from DropBox. Attempting to do so results in a download of an HTML page that appears to contain a 403 forbidden message, almost as if the login session information wasn't persisted across to the connection that attempts to handle the actual download request. This occurs for both attempts to download individual files, as well as the functionality that allows one to download an entire folder as a zip. Furthermore, it doesn't appear to matter if one selects the function via the right click context menu, or one of the buttons across the top.

This is on hrev47169.

[pulkomandy]

Duplicate of #10820.