Set installation to fcm now.

The push adapter actually ignores the push type and falls back to the device type.  It should be OK to classify these pushes as FCM.

https://github.com/parse-community/parse-server-push-adapter/blob/master/src/PushAdapterUtils.js#L20
https://github.com/parse-community/parse-server-push-adapter/blob/master/src/ParsePushAdapter.js#L35

We should move off the parse-server GCM module because the FCM send only needs the GCloud project instead of sender ID.

Author: rogerhu

fcm/src/main/java/com/parse/fcm/ParseFirebaseJobService.java

@@ -26,6 +26,7 @@
 public class ParseFirebaseJobService extends JobService {
 
     private static final String JOB_TAG_UPLOAD_TOKEN = "upload-token";
+    private static final String PUSH_TYPE = "fcm";
 
     static Job createJob(FirebaseJobDispatcher dispatcher) {
         return dispatcher.newJobBuilder()
@@ -50,7 +51,7 @@ public boolean onStartJob(final JobParameters job) {
         if (installation != null && token != null) {
             installation.setDeviceToken(token);
             //even though this is FCM, calling it gcm will work on the backend
-            installation.setPushType("gcm");
+            installation.setPushType(PUSH_TYPE);
             installation.saveInBackground(new SaveCallback() {
                 @Override
                 public void done(ParseException e) {