Fix test regression

src/style_manager/model/Layer.js

@@ -18,7 +18,10 @@ module.exports = Backbone.Model.extend({
       'properties',
       properties instanceof Properties ? properties : new Properties(properties)
     );
-    this.get('properties').forEach(item => item.parent = this.collection.property);
+    this.get('properties').forEach(item => {
+      const { collection } = this;
+      item.parent = collection && collection.property;
+    });
 
     // If there is no value I'll try to get it from values
     // I need value setted to make preview working

test/specs/style_manager/model/Models.js

@@ -703,7 +703,7 @@ module.exports = {
               property: 'border-top-left-radius',
               type: 'integer',
               units: ['px', '%'],
-              defaults: 0,
+              defaults: '0px',
               min: 0
             },
             {
@@ -711,21 +711,21 @@ module.exports = {
               type: 'integer',
               units: ['px', '%'],
               min: 0,
-              defaults: 0
+              defaults: '0px'
             },
             {
               property: 'border-bottom-left-radius',
               type: 'integer',
               units: ['px', '%'],
               min: 0,
-              defaults: 0
+              defaults: '0px'
             },
             {
               property: 'border-bottom-right-radius',
               type: 'integer',
               units: ['px', '%'],
               min: 0,
-              defaults: 0
+              defaults: '0px'
             }
           ]
         };