Bug 9737 - Local Covers sometimes appear then disappear on OPAC Search Results/Lists

Bug 9737 - Local Covers sometimes appear then disappear on OPAC Search Results/Lists

The current problem:

When the verify_images() function runs from amazonimages.js, it loops
through every img element and selects the elements that come from Amazon
sources.

However, if the height/width is 1 (i.e. Amazon passes off a blank image)
or if the img element's complete property is null or non-existent, then
it searches for the parent node and re-writes the HTML with the "No
Cover Image Available" (NO_AMAZON_IMAGE) text, even though that parent
node might contain other img elements that have images available (from
Google, local images, etc)!

Proposed fix:

Wrap the Amazon image in a span tag (as we do with the Google and local
covers), so that it re-writes the HTML within that parent span, rather
than the parent anchor which contains all the other images.

To test:

1) Turn on the OPACAmazonCoverImages, GoogleJackets, and
   OPACLocalCoverImages system preferences
2) Replace the ISBN in one of your records with 9780615352435
3) Now load a local cover image for that record
4) Search for that record (but make sure you're vague enough to have
   multiple search results)
5) For a split second, you may notice the local cover image appears before being replaced by a "No Cover Image Available".

Now apply this patch

6) Refresh your search results page
7) You should now see your local cover image, PLUS the "No Cover Image
   Available" for the Amazon image, and whatever other graphics/"no
   cover image available" "graphics" for the Google Jackets.

To be comprehensive, try the same set of steps using the OPAC Lists
rather than the OPAC Search Results

Signed-off-by: Owen Leonard <oleonard@myacpl.org>
Signed-off-by: Jonathan Druart <jonathan.druart@biblibre.com>
Signed-off-by: Chris Cormack <chris@bigballofwax.co.nz>