- if multiaccount settings are saved on top of an empty map or nil,
this means something went wrong, the state of the app is unstable,
and actually saving will result in loss of data. It should never
happen, but if it does, throw and error and abort.
- sometimes two fxs are merged when they shouldn't, this is caused by
bugs and should never happen, but if it does, throw an error with arguments
for both effects to help localize the error
Signed-off-by: yenda <eric@status.im>
c047b588ed