Protect GrantCredentialsPermissionActivity against overlay. am: f45dcfe1f5 am: 3f47c701f1

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/13029378

Change-Id: I59ea6157c2646c0398111718cff4af51cd4245d8

core/java/android/accounts/GrantCredentialsPermissionActivity.java

@@ -47,6 +47,9 @@ public class GrantCredentialsPermissionActivity extends Activity implements View
 
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
+        getWindow().addSystemFlags(
+                android.view.WindowManager.LayoutParams
+                        .SYSTEM_FLAG_HIDE_NON_SYSTEM_OVERLAY_WINDOWS);
         setContentView(R.layout.grant_credentials_permission);
         setTitle(R.string.grant_permissions_header_text);