`Comment Selection` command on disjoint multi-line selection does not behave as expected

[JosephPecoraro]

The Comment Selection command on disjoint multi-line selection does not behave as expected.

Sample text file:

1 one
2 two
3 three
4

Steps to reproduce:

1. Hold Command and triple click on line 1 and line 3 to have both lines completely selected
2. Bundles > Source > Comments > Comment Selection (⌘/)
   => Unexpected result

Actual Result:

one
two
# one
#
# three

Expected Result:

# one
two
# three