Now, the UTF8 migration doesn't rely one indexes specified in the .xml files. Instead, for each table, it fetches all the existing indexes from db, drop them all and, after utf-8 conversion, rebuilds them.
Now, the UTF8 migration doesn't rely one indexes specified in the .xml files. Instead,
for each table, it fetches all the existing indexes from db, drop them all and, after
utf-8 conversion, rebuilds them.

With this, all the indexes will be exactly the same than the original present in DB, no matter
of their names nor anything else.

So, starting now, to provide a sucessful UTF8 migration we only have to keep updated the
fields .xml info. Bye, bye indexes info.

dilawar/moodle