My upload to firebase won't work and it seems like I need to add the line
window.XMLHttpRequest = RNFetchBlob.polyfill.XMLHttpRequest;
To prior to my class declaration, but when I do I just get this error:

I'm using React Native v0.43.0-rc.4 and the newest beta of react-native-fetch-blob.
My upload to firebase won't work and it seems like I need to add the line

window.XMLHttpRequest = RNFetchBlob.polyfill.XMLHttpRequest;To prior to my class declaration, but when I do I just get this error:
I'm using React Native v0.43.0-rc.4 and the newest beta of react-native-fetch-blob.