GNOME developer Tobias Mueller has developed a small Python script now for NetworkManager that allows exporting WiFi configurations from the Linux desktop that can then be easily read by Android devices. Following that, Tobias also wrote a Python script for being able to read these QR codes of network information and add it to NetworkManager.
For now though, this QR reading/writing support hasn't been integrated into NetworkManager, but it sure would be handy to see it rather than having to use some external scripts for this support. It sure would be handy to see, particularly for mobile devices.
If you are curious about these scripts for the support or the process of storing WiFi information in barcodes, see Tobias' blog post.