Log Message:
Update drupal7 to 7.28.

Drupal 7.28, 2014-05-08
-----------------------
- Fixed a regression introduced in Drupal 7.27 that caused JavaScript to break
  on older browsers (such as Internet Explorer 8 and earlier) when Ajax was
  used.
- Increased the timeout used by the Update Manager module when it fetches data
  from drupal.org (from 5 seconds to 30 seconds), to work around a problem
  which causes incomplete information about security updates to be presented to
  site administrators. This fix may lead to a performance slowdown on the
  Update Manager administration pages, when installing Drupal distributions,
  and (for sites that use the automated cron feature) on occasional page loads
  by site visitors.
- Fixed the behavior of the token system's "[node:summary]" token when \ 
the body
  field does not have a manual summary.
- Changed the behavior of db_query_temporary() so that it works on SELECT
  queries even when they have leading comments/whitespace. A side effect of
  this fix is that db_query_temporary() will now fail with an error if it is
  ever used on non-SELECT queries.
- Added a "node_admin_filter" tag to the database query used to build \ 
the list
  of nodes on the content administration page, to make it easier to alter.
- Made the cron queue system log any exceptions that are thrown while an item
  in the queue is being processed, rather than stopping the entire PHP request.
- Improved screen reader support by adding an aria-live HTML attribute to file
  upload fields when there is an error uploading the file (minor markup
  change).
- Made the pager on the Tracker module listing pages show the same number of
  items as other pagers throughout Drupal core (minor UI change).
- Fixed a bug which caused caches not to be properly cleared when a file entity
  was saved or deleted.
- Added several missing countries to the default list returned by
  country_get_list() (string change).
- Replaced the term "weight" with "influence" in the content \ 
ranking settings
  for search, and added help text for administrators (string change).
- Fixed untranslatable text strings in the administrative interface for the
  "Crop" effect provided by the Image module (minor string change).
- Fixed a bug in the Taxonomy module update function introduced in Drupal 7.26
  that caused memory and CPU problems on sites with very large numbers of
  unpublished nodes.
- Numerous small bug fixes.
- Numerous API documentation improvements.
- Additional automated test coverage.