Determine whether buffer of PROCESS will inherit coding-system.
If the second argument FLAG is non-nil, then the variable
`buffer-file-coding-system' of the buffer associated with PROCESS
will be bound to the value of the coding system used to decode
the process output.
This is useful when the coding system specified for the process buffer
leaves either the character code conversion or the end-of-line conversion
unspecified, or if the coding system used to decode the process output
is more appropriate for saving the process buffer.
Binding the variable `inherit-process-coding-system' to non-nil before
starting the process is an alternative way of setting the inherit flag
for the process which will run. This function returns FLAG. (fn PROCESS FLAG)