convertEntities() used before it is defined

The convertEntities function was defined in utils.js, but if you use script concatenation this file would be included after it is needed. Because it was in a try-catch clause, the error was not (always) noticed.

The solution is to include the convertEntities function before this code is loaded. In WordPress 3.1 this is now included in l10n.js, which you cannot disable. A quick and dirty solution would be to copy this code and write it at the top of each page, so you are sure it is available.