code: private static int[] getCornerColors(@NonNull Orientation orientation,
                                           @ColorInt final int horizontalShadowColor,
                                           @ColorInt final int verticalShadowColor) {
          switch (orientation) {
              case TOP_RIGHT:
                  return new int[]{horizontalShadowColor, verticalShadowColor};
              case TOP_LEFT:
              case BOTTOM_LEFT:
              case BOTTOM_RIGHT:
                  return new int[]{verticalShadowColor, horizontalShadowColor};
              default:
                  throw new IllegalArgumentException("Invalid orientation: " + orientation);
          }
      }
docs: Returns an array, which contains the colors, which should be used to draw a shadow, which is
  located at a corner of an elevated view.
  
  @param orientation
  TThe orientation of the shadow in relation to the elevated view as a value of the
  enum {@link Orientation}. The orientation may either be <code>TOP_LEFT</code>,
  <code>TOP_RIGHT</code>, <code>BOTTOM_LEFT</code> or <code>BOTTOM_RIGHT</code>
  @param horizontalShadowColor
  The color of the shadow, which is located next to the corner in horizontal direction,
  as an {@link Integer} value
  @param verticalShadowColor
  The color of the shadow, which is located next to the corner in vertical direction,
  as an {@link Integer}  value
  @return The colors, which should be used to draw the shadow, as an {@link Integer} array