[#1916] Moooaar nullability annotations

Author: jossiwolf

app/src/main/java/com/firebase/uidemo/auth/AnonymousUpgradeActivity.java

@@ -210,7 +210,7 @@ private String getUserIdentifier(FirebaseUser user) {
     }
 
     @Override
-    public void onActivityResult(FirebaseAuthUIAuthenticationResult result) {
+    public void onActivityResult(@NonNull FirebaseAuthUIAuthenticationResult result) {
         handleSignInResult(result.getResultCode(), result.getIdpResponse());
     }
 }

app/src/main/java/com/firebase/uidemo/auth/AuthUiActivity.java

@@ -525,7 +525,7 @@ private void showSnackbar(@StringRes int errorMessageRes) {
     }
 
     @Override
-    public void onActivityResult(FirebaseAuthUIAuthenticationResult result) {
+    public void onActivityResult(@NonNull FirebaseAuthUIAuthenticationResult result) {
         // Successfully signed in
         IdpResponse response = result.getIdpResponse();
         handleSignInResponse(result.getResultCode(), response);

auth/src/main/java/com/firebase/ui/auth/FirebaseAuthUIActivityResultContract.java

@@ -26,6 +26,7 @@ public Intent createIntent(@NonNull Context context, Intent input) {
     }
 
     @Override
+    @NonNull
     public FirebaseAuthUIAuthenticationResult parseResult(int resultCode, @Nullable Intent intent) {
         return new FirebaseAuthUIAuthenticationResult(resultCode, IdpResponse.fromResultIntent(intent));
     }