Fix #327
Fix #327

The cause  is https://github.com/apache/cordova-ios/pull/310/files.
ceisinger/cordova-plugin-firebase,arnesson/cordova-plugin-firebase,ceisinger/cordova-plugin-firebase,Vying/cordova-plugin-firebase,Vying/cordova-plugin-firebase,arnesson/cordova-plugin-firebase,ceisinger/cordova-plugin-firebase,ceisinger/cordova-plugin-firebase,arnesson/cordova-plugin-firebase,arnesson/cordova-plugin-firebase,Vying/cordova-plugin-firebase,DigitalsunrayMedia/cordova-plugin-firebase,DigitalsunrayMedia/cordova-plugin-firebase,DigitalsunrayMedia/cordova-plugin-firebase