docs: private void addUnmatched(@NonNull ArrayMap<View, TransitionValues> unmatchedStart,
                                @NonNull ArrayMap<View, TransitionValues> unmatchedEnd) {
          // Views that only exist in the start Scene
          for (int i = 0; i < unmatchedStart.size(); i++) {
              mStartValuesList.add(unmatchedStart.valueAt(i));
              mEndValuesList.add(null);
          }
  
          // Views that only exist in the end Scene
          for (int i = 0; i < unmatchedEnd.size(); i++) {
              mEndValuesList.add(unmatchedEnd.valueAt(i));
              mStartValuesList.add(null);
          }
      }