Tab auto-completion removes quotes from variables even when it shouldn't

[Pedro Gimeno]

Bash Version: 4.4
Patch Level: 12
Release Status: release

Tested also in the last version from this unofficial mirror: 
https://github.com/bminor/bash so I guess it's still a problem.

Tab auto-completion removes quotes from variables even when it shouldn't.

Test case:
$ mkdir 'a b'
$ touch 'a b'/c
$ i='a b'
$ ls "$i"/<press tab here>

After pressing tab, the last line becomes:

$ ls $i/c

When pressing enter, the expected result happens:

ls: cannot access 'a': No such file or directory
ls: cannot access 'b/c': No such file or directory

I expected quoted variables to preserve the quotes when auto-completing with 
tab.