Revert "defined?在ruby2后返回永远为真", tested in Rails 5 API, should using defined?
Revert "defined?在ruby2后返回永远为真", tested in Rails 5 API, should using defined?

This reverts commit f96ae1727eb62569c771f6d66c5b9014b8a4e9c6.

skinnyworm/wechat-rails,TangMonk/wechat,zfben/wechat,wolflee/wechat-rails,Eric-Guo/wechat,Eric-Guo/wechat,wolflee/wechat-rails