bug: filebrowserImageBrowseLinkUrl config isn't used

It appears that the value specified for config.filebrowserImageBrowseLinkUrl isn't used. Instead, the setting for filebrowserImageBrowseUrl is used. This seems like a bug.

I've confirmed that this is the case in 3.1 and 3.4b. I assume that it's a bug in 3.2 as well.