Little code refactoring

git-svn-id: svn://svn.forge.objectweb.org/svnroot/spagobi/V_4.x/Server/trunk@21360 99afaf0d-6903-0410-885a-c66a8bbb5f81
Bug fix: an error occurred when creating a worksheet document starting from a persisted Qbe dataset, when double-clicking on an attribute to set a global filter

git-svn-id: svn://svn.forge.objectweb.org/svnroot/spagobi/V_4.x/Server/trunk@21361 99afaf0d-6903-0410-885a-c66a8bbb5f81