title: Removing Firebase from project without losing GCM
body: <p>In starters, I have read this thread: <a href="https://stackoverflow.com/questions/38120862/remove-firebase-analytics-from-android-app-completely">Remove firebase analytics from android app completely</a> - but it didn't give me answer to my problem. In app I am developing I had to implement push notifications. I wanted to start with GCM, then I discovered Firebase. I added it to my project and then realized the pricing on it. I decided to scrap it and come back to GCM. I removed all Firebase-related stuff from my code and I thought everything will be allright.</p>
  
  <p>Lately I started to work on an optimization of that app and noticed certain information in debug log:</p>
  
  <pre><code>07-06 07:03:39.310 13286-13474/com.example.myapp D/FirebaseInstanceId: background sync failed: MISSING_INSTANCEID_SERVICE, retry in 20s
  </code></pre>
  
  <p>It goes on and on, doubling the retry time. I'm not sure how does it affect my app (hovewer, once I saw big loss of frames everytime it happened), but I am completely dumbfound about Firebase still being in my app. Only instances of it are located in build folder, which means I can't erase them myself. I tried to use configurations, I tried to exclude this for GCM exclusively, still nothing.</p>
  
  <pre><code>configurations {
      all*.exclude group: 'com.google.firebase', module: 'firebase-core'
      all*.exclude group: 'com.google.firebase', module: 'firebase-iid'
      all*.exclude group: 'com.google.firebase', module: 'firebase-common'
  }
  </code></pre>
  
  <p>It is right in the beggining of my build.gradle file. Not sure if it's important, but Android Studio tells me that it can't resolve symbol "exclude" in here. I also tried to put this in compile GCM (of course without all* in there), but it didn't change anything.</p>
  
  <p>tl;dr I want to get rid of Firebase and still have GCM in my project. Any ideas?</p>