Bug 10466: fix glitch in OPAC display of titles saved to list

When displaying (in the OPAC) the set of records saved to a list,
an apparently random number (typically 33 or 34) is sometimes
displayed at the end of the publication description.  In particular,
this can occur when XSLT is *not* being used to display search results;
this patch corrects the problem.

Now for the technical details:

This patch checks to see if "size" is undefined. If it is, we add a
blank (i.e. "") value to it in place of undef.

If we do not do this, calling "itemloo.size" will return the size
of the "itemloo" hash, rather than the value for the "size" key.

This is because "size" is a virtual method in Template Toolkit. It's
uncertain why the value is retrieved for the "size" key when there is
a defined value and why TT doesn't use the method instead, and that
it uses "size" as a method only if there is either no "size" key or
if the value tied to the "size" key is null/undef. This might be a
feature or it might be a bug in TT...

In the meantime, we will check to see if it's undefined. If it is,
we'll give it a value.

This bug has been identified in the opac-search.pl, search.pl and
addbooks.pl pages before. To address it, we're currently checking
if there is a "size" key, and if not...we're adding one with a blank
value.

This patch takes up that same idea, although I think it might be better
to rename the variable before passing it to TT in case the behaviour
of TT changes in the future in regards to how it handles virtual
methods.

N.B. Obviously, this only affects users not using XSLTs.

--

Test Plan:

Before applying the patch:

0) Make sure you have opac search result XSLT turned off

1) Find bib records that do not have a 300$c (Dimensions) value.
2) Find bib records that do have a 300$c (Dimensions) value.

(N.B. These values should be stored in the `size` column of biblioitems).

3) Add items from both sets of records to a List
4) Note that records without a 300$c will display a number at the end
of the "Publication" description/string. It should be something like
33 or 34 in most cases.
5) Note that records with a 300$c don't display this number. They just
show the value from 300$c.

Apply the patch.

6) Clear your cache, refresh the page, etc.
7) Note that the number (e.g. 33 or 34) has disappeared from the end
of the "Publication" description/string.

Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Added a small comment at the end of this one line.

Signed-off-by: Galen Charlton <gmc@esilibrary.com>