Fix echostr bug, should only check at enterprise mode.
Fix echostr bug, should only check at enterprise mode.

Eric-Guo/wechat,TangMonk/wechat,wolflee/wechat-rails,yxf/wechat,EndingChaung/wechat,Eric-Guo/wechat,skinnyworm/wechat-rails,zfben/wechat,JeeLiu/wechat,wolflee/wechat-rails