Comment 1 for bug 1747963

Here's the branch:

http://git.evergreen-ils.org/?p=working/Evergreen.git;a=shortlog;h=refs/heads/user/rsteed/lp1747963_checkin_trim_list_fix

And from the commit message:

    The use of splice() here caused buggy behavior and seemed to be a typo,
    so I tried using slice() instead. But that still didn't work correctly.
    The list stopped adding items after it reached 21 total, so scanning a
    new barcode didn't add it to the list but only refreshed the list.

    Instead, this commit sets the length of the array to 20, which shortens
    the array as described in the MDN documentation for Array.length. Now it
    behaves like it did in the XUL client.