The web process is creating its config dir (for storing its read-only
keyfile view of Epiphany settings) in the wrong place, under
~/.local/share/epiphany/config instead of under ~/.config/epiphany.
Problem is we take the codepath in ephy_file_helpers_init() for
non-default profile dirs. We're supposed to pass NULL for the profile
dir when we want the default dir, not pass the path to the default dir.