Rename user limits api by user limits backend

lib/cartodb/api/template/tile-template-controller.js

@@ -17,14 +17,14 @@ function TileTemplateController (
     surrogateKeysCache,
     pgConnection,
     authBackend,
-    userLimitsApi
+    userLimitsBackend
 ) {
     this.namedMapProviderCache = namedMapProviderCache;
     this.tileBackend = tileBackend;
     this.surrogateKeysCache = surrogateKeysCache;
     this.pgConnection = pgConnection;
     this.authBackend = authBackend;
-    this.userLimitsApi = userLimitsApi;
+    this.userLimitsBackend = userLimitsBackend;
 }
 
 module.exports = TileTemplateController;
@@ -35,7 +35,7 @@ TileTemplateController.prototype.register = function (templateRouter) {
         credentials(),
         authorize(this.authBackend),
         dbConnSetup(this.pgConnection),
-        rateLimit(this.userLimitsApi, RATE_LIMIT_ENDPOINTS_GROUPS.NAMED_TILES),
+        rateLimit(this.userLimitsBackend, RATE_LIMIT_ENDPOINTS_GROUPS.NAMED_TILES),
         cleanUpQueryParams(),
         namedMapProvider({
             namedMapProviderCache: this.namedMapProviderCache,