sale-api code review rewrite

@@ -37,14 +37,14 @@ exports.getSaleGoodsList = (params) => {
 
     let tempChannel = _.isEmpty(params.channel) ? 'boys' : params.channel;
 
-    params = Object.assign({
+    Object.assign(params, {
         method: 'app.search.sales',
         limit: 60,
         order: 's_t_desc',
         productSize: '384x511',
         yh_channel: yhChannel[tempChannel].channel
-    }, params);
-    params.yh_channel = yhChannel[tempChannel].channel;
+    });
+
     return api.get('', sign.apiSign(params));
 };