Merge branch 'feature/wkwebview' into 'release/6.8.8'

fix issue



See merge request !30

@@ -140,6 +140,7 @@ const render = (route) => {
           asyncScripts = asyncLoadScripts(scripts);
         }
         if (req.get('User-Agent').indexOf('yoho-protocol') >= 0 &&
+          route.cacheKey &&
           route.cacheKey.indexOf('$yoho-protocol') >= 0 &&
           isYohoProtocol) {
           styles = styles.replace(/"\/\//g, '"yoho-protocol://');
@@ -213,6 +214,7 @@ const devRender = (route) => {
           let {styles, scripts, resources, states, html} = msg;
 
           if (req.get('User-Agent').indexOf('yoho-protocol') >= 0 &&
+            route.cacheKey &&
             route.cacheKey.indexOf('$yoho-protocol') >= 0) {
             styles = styles.replace(/"\/\//g, '"yoho-protocol://');
           }