code: function( root ) { //jshint ignore:line
          for ( var i = 0; i < preInitPlugins.length; i++ ) {
              var thisLevel = preInitPlugins[ i ];
              if ( thisLevel !== undefined ) {
                  for ( var j = 0; j < thisLevel.length; j++ ) {
                      thisLevel[ j ]( root );
                  }
              }
          }
      }
docs: Called at beginning of init, to execute all pre-init plugins.