FC Barcelona’s finest era in the club’s 123-year history came between 2008 and 2012, when a host of La Masia graduates including Lionel Messi, Andrés Iniesta, Sergio Busquets and Xavi Hernández impressed in a Blaugrana side that won two Champions League titles and three La Liga titles under Pep Guardiola.   The Catalan club’s representatives…