Data editor duplicates pairs of backslashes (PR#11897)

Full_Name: Magnus Torfason
Version: 2.7.0
OS: Windows Vista
Submission from: (NULL) (128.59.140.167)


Each time a string is edited in the data editor (on Windows at least), any pairs
of backslashes (an escaped backslash) are duplicated on each edit of the string.
Note that one must actually double click the value for the bug to show up.

Behavior/Replication:

# Create data frame
d=data.frame(a="\\")
# Edit data frame, and while editing, double click 
# value several times to edit (selecting something 
# different between each doubleclick)
d=edit(d)
d

a
1 \\\\\\\\\\\\\\\\