code: @Nullable
    static Drawable maybeWrapWithMatrix(
        @Nullable Drawable drawable,
        @Nullable Matrix matrix) {
      if (drawable == null || matrix == null) {
        return drawable;
      }
      return new MatrixDrawable(drawable, matrix);
    }
docs: Wraps the given drawable with a new {@link MatrixDrawable}.
  
  <p> If the provided drawable or matrix is null, the given drawable is returned without
  being wrapped.
  
  @return the wrapping matrix drawable, or the original drawable if the wrapping didn't
  take place