When doing a backup or restore operation with the normal user interface,
if there is anything in the backup/restore log, it will now be displayed
at the end of the process below the Continue button.
If you have developer debugging enabled, it sets the display level to
LOG_DEBUG and there will always be content in the log. Otherwise, it
uses LOG_INFO which generally means the log is empty, and nothing
displays (no visible change for users).
Adds 'Preparing page display' progress bars for user interface pages
if they take a long time to display.
Also adds changes where other parts of the backup progress timed out on
long backups. After this change, and MDL-41838, it is finally possible on
my dev server to successfully back up the 'XL' test course.