Fix a bug that was making it impossible to display billing information in the android app.

rules/lantern-dataaccess-rules/src/main/java/com/lanternsoftware/dataaccess/rules/MongoRulesDataAccess.java

@@ -64,6 +64,11 @@ public class MongoRulesDataAccess implements RulesDataAccess {
 		proxy.save(_device);
 	}
 
+	@Override
+	public void removeFcmDevice(String _id) {
+		proxy.delete(FcmDevice.class, new DaoQuery("_id", _id));
+	}
+
 	@Override
 	public List<FcmDevice> getFcmDevicesForAccount(int _accountId) {
 		return proxy.query(FcmDevice.class, new DaoQuery("account_id", _accountId));

rules/lantern-dataaccess-rules/src/main/java/com/lanternsoftware/dataaccess/rules/RulesDataAccess.java

@@ -17,5 +17,6 @@ public interface RulesDataAccess {
 	Event getMostRecentEvent(int _accountId, EventType _type, String _sourceId);
 	List<Event> getEvents(int _accountId, EventType _type, String _sourceId, Date _from, Date _to);
 	void putFcmDevice(FcmDevice _device);
+	void removeFcmDevice(String _id);
 	List<FcmDevice> getFcmDevicesForAccount(int _accountId);
 }