Every time I install the firebase_auth library This error appears

[abozozzaher]

D:\FlutterApps\Android\src\flutter.pub-cache\hosted\pub.dartlang.org\firebase_auth-0.6.2+1\android\src\main\java\io\flutter\plugins\firebaseauth\FirebaseAuthPlugin.java:8: error: package android.support.annotation does not exist
[ +1 ms] import android.support.annotation.NonNull;
[ ] ^
[ ] D:\FlutterApps\Android\src\flutter.pub-cache\hosted\pub.dartlang.org\firebase_auth-0.6.2+1\android\src\main\java\io\flutter\plugins\firebaseauth\FirebaseAuthPlugin.java:538: error: cannot find symbol
[ ] public void onComplete(@nonnull Task task) {
[ ] ^
[ ] symbol: class NonNull
[ ] location: class FirebaseAuthPlugin.SignInCompleteListener
[ ] D:\FlutterApps\Android\src\flutter.pub-cache\hosted\pub.dartlang.org\firebase_auth-0.6.2+1\android\src\main\java\io\flutter\plugins\firebaseauth\FirebaseAuthPlugin.java:558: error: cannot find symbol
[ ] public void onComplete(@nonnull Task task) {