docs: @NonNull
      @Override
      public TransitionSet setDuration(long duration) {
          super.setDuration(duration);
          if (mDuration >= 0 && mTransitions != null) {
              int numTransitions = mTransitions.size();
              for (int i = 0; i < numTransitions; ++i) {
                  mTransitions.get(i).setDuration(duration);
              }
          }
          return this;
      }