title: FIrebase Cloud Messaging, cannot resolve dependency com.google.firebase:firebase-core:9.0.2
body: <p>I was trying to write an application using Firebase Cloud Messaging as per the guidelines given <a href="https://firebase.google.com/docs/android/setup#prerequisites" rel="nofollow">here</a>, but I'm struck in adding the dependency for implementing FCM (com.google.firebase:firebase-core:9.0.2). Every time I try to add it via project structure, it won't list the dependency in the search results. When I try to add it in app level gradle, it gives me an error that the dependency cannot be resolved. I don't know where I'm going wrong but please help me out with this. </p>