mysql database connections will be migrated
This answer was given at the MySQL forum by Javier Treviño from the  MySQL on Windows Team:


  Some products are able to share connection information to MySQL Server
  instances with MySQL Workbench. The products that do this are MySQL
  for Excel, MySQL Notifier and MySQL for Visual Studio. 
  
  By sharing connection information this means that if MySQL Workbench
  is installed in the same computer, all of these programs will attempt
  to use the same configuration file where MySQL Workbench stores the
  information about connections. 
  
  So, if any of the 3 aforementioned products are installed but MySQL
  Workbench is not, they will fallback to use their own separate
  configuration file to store connection information, but as soon as
  they detect MySQL Workbench is present, they will attempt to migrate
  or move the connections stored in the separate configuration file to
  the file MySQL Workbench uses. 
  
  The product presents a dialog with the message you have been talking
  about in this forum thread. You should notice there is a More Info
  button displayed in that dialog. If you click it an information
  message like this will be shown: 
  
  
    {APP_NAME} now works with the connections file used by MySQL Workbench
    if it is installed. 
    
    {APP_NAME} will attempt to merge all existing connections with MySQL
    Workbench and in order to do this MySQL Workbench must not be running.
    
    Please make sure MySQL Workbench is closed to continue with the
    merging operation.  If you choose not to migrate connections now, you
    will be prompted later to perform the migration. 
  
  
  Also note that in the latest versions of the 3 aforementioned products
  the migration of connection information can be delayed to be done at a
  later time or delayed indefinitely, which means the connection
  information will remain in the product's configuration file until a
  manual migration of this information is performed.