Comment 2 for bug 979227

A partial solution at least. Script attached was used to test and perform the switch over to utf8 within work. I can't confirm whether there may be issues with other services accessing the same DB subsequently, but it did work as expected within Gerrit.

Only place I noticed any charset conversion issues, is within the patch_comments table. However I suspect depending on usage, the following is a more complete list of table.fields that need to be checked for conversion issues:
account_agreements.review_comments
account_group_agreements.review_comments
account_groups.description
change_messages.message
patch_comments.message

Those are the only text fields which are in any way free form. All the remaining varchar fields are restricted to what can be accepted into them due to usage.