Use req2params middleware for dataview endpoint

lib/cartodb/controllers/layergroup.js

@@ -102,6 +102,7 @@ LayergroupController.prototype.register = function(app) {
         cors(),
         userMiddleware,
         allowQueryParams(allowedDataviewQueryParams),
+        this.req2paramsMiddleware,
         this.dataview.bind(this)
     );
 
@@ -110,6 +111,7 @@ LayergroupController.prototype.register = function(app) {
         cors(),
         userMiddleware,
         allowQueryParams(allowedDataviewQueryParams),
+        this.req2paramsMiddleware,
         this.dataview.bind(this)
     );
 
@@ -166,12 +168,7 @@ LayergroupController.prototype.dataview = function(req, res, next) {
     var self = this;
 
     step(
-        function setupParams() {
-            self.req2params(req, res, this);
-        },
-        function retrieveDataview(err) {
-            assert.ifError(err);
-
+        function retrieveDataview() {
             var mapConfigProvider = new MapStoreMapConfigProvider(
                 self.mapStore, req.context.user, self.userLimitsApi, req.params
             );
@@ -188,7 +185,6 @@ LayergroupController.prototype.dataview = function(req, res, next) {
             }
         }
     );
-
 };
 
 LayergroupController.prototype.dataviewSearch = function(req, res, next) {