Make sure to always default to the Downloads directory in case a file
dialog is opened and unveil(2) is used.
This fixes the issue when another program not using unveil(2) changes
the last used path of the file dialog and then the file dialog opened
by chrome will get stuck inside a non-existent directory.
To make sure that the ~/Downloads XDG directory is always available
for glib to pick up, the chrome wrapper script will check if the
~/.config/user-dirs.dirs does not exist and create it with one entry
configured: XDG_DOWNLOAD_DIR="$HOME/Downloads"
UnifiedSplitRaw
