Overviews adapter with getMapConfig interface

lib/cartodb/controllers/map.js

@@ -188,17 +188,12 @@ MapController.prototype.create = function(req, res, prepareConfigFn) {
         function addOverviewsInformation(err, requestMapConfig, datasource) {
             assert.ifError(err);
             var next = this;
-            self.overviewsAdapter.getLayers(
-                req.context.user, requestMapConfig.layers, analysesResults,
-                function(err, layers) {
+            self.overviewsAdapter.getMapConfig(req.context.user, requestMapConfig, analysesResults,
+                function(err, requestMapConfig) {
                     if (err) {
                         return next(err);
                     }
 
-                    if (layers) {
-                        requestMapConfig.layers = layers;
-                    }
-
                     return next(null, requestMapConfig, datasource);
                 }
             );

lib/cartodb/models/mapconfig/adapter/mapconfig-overviews-adapter.js

@@ -9,11 +9,13 @@ function MapConfigOverviewsAdapter(overviewsMetadataApi, filterStatsApi) {
 
 module.exports = MapConfigOverviewsAdapter;
 
-MapConfigOverviewsAdapter.prototype.getLayers = function(username, layers, analysesResults, callback) {
+MapConfigOverviewsAdapter.prototype.getMapConfig = function(username, requestMapConfig, analysesResults, callback) {
   var self = this;
 
+  var layers = requestMapConfig.layers;
+
   if (!layers || layers.length === 0) {
-      return callback(null, layers);
+      return callback(null, requestMapConfig);
   }
 
   var augmentLayersQueue = queue(layers.length);
@@ -85,7 +87,9 @@ MapConfigOverviewsAdapter.prototype.getLayers = function(username, layers, analy
         return callback(new Error('Missing layers array from layergroup config'));
     }
 
-    return callback(null, layers);
+    requestMapConfig.layers = layers;
+
+    return callback(null, requestMapConfig);
   }
 
   layers.forEach(function(layer) {

lib/cartodb/models/mapconfig/provider/named-map-provider.js

@@ -145,15 +145,11 @@ NamedMapMapConfigProvider.prototype.getMapConfig = function(callback) {
             assert.ifError(err);
             var next = this;
 
-            self.overviewsAdapter.getLayers(self.owner, _mapConfig.layers, self.analysesResults, function(err, layers) {
+            self.overviewsAdapter.getMapConfig(self.owner, _mapConfig, self.analysesResults, function(err, _mapConfig) {
                 if (err) {
                     return next(err);
                 }
 
-                if (layers) {
-                    _mapConfig.layers = layers;
-                }
-
                 return next(null, _mapConfig, datasource);
             });
         },