Fixed some refactoring errors of mine. This should cure CORE-4334: Resources (e.g. sort files) owned by trigger may not be released when it's interrupted asynchronously.

git-svn-id: svn+ssh://svn.code.sf.net/p/firebird/code/firebird/trunk@59107 65644016-39b1-43b1-bf79-96bc8fe82c15