which is just a #define to g_assert for now, but can now easily be
turned into something that does some nicer debugging using our new
stack trace infrastructure. This commit also reverts all constructed()
functions to use assert again.
We need to mount every non-native GFile's volume, regardless of
whether the file procedure uses GIO directly or needs file-remote to
download/upload the file. Move the entire mount logic to a new
file-remote function and change gimp-gui.c and gui-vtable.c to only
return a GMountOperation. Try to mount every non-native file in
file-open.c and file-save.c and bail out if mounting fails. Simplify
the uploading and downloading code accordingly.
- change start() and set_text() to use "format" and "..." instead of
"message", allowing to format progress messages in place
- s/cancelable/cancellable/
- move "cancellable" to be the second argument of start()
