public Builder setVisibility(@NotificationVisibility int visibility) {
            mVisibility = visibility;
            return this;
        }
Sets {@link Notification#visibility}.

@param visibility One of {@link Notification#VISIBILITY_PRIVATE} (the default),
                  {@link Notification#VISIBILITY_PUBLIC}, or
                  {@link Notification#VISIBILITY_SECRET}.
android/android_framework/base/src/main/java/github/tornaco/android/thanos/core/compat/NotificationCompat.java