code: public CloseableReference<Bitmap> createBitmap(
        Bitmap source,
        int x,
        int y,
        int width,
        int height) {
      return createBitmap(source, x, y, width, height, null);
    }
docs: Creates a bitmap from the specified subset of the source
  bitmap. It is initialized with the same density as the original bitmap.
  
  @param source   The bitmap we are subsetting
  @param x        The x coordinate of the first pixel in source
  @param y        The y coordinate of the first pixel in source
  @param width    The number of pixels in each row
  @param height   The number of rows
  @return a reference to the bitmap
  @throws IllegalArgumentException if the x, y, width, height values are
  outside of the dimensions of the source bitmap, or width is <= 0,
  or height is <= 0
  @throws TooManyBitmapsException if the pool is full
  @throws java.lang.OutOfMemoryError if the Bitmap cannot be allocated