bug#22763: 25.1.50; Feature Request -- A faster method to obtain line number at position.

[Ben Levy]

For this section in the line-number-at-pos code:

/* Check that POSITION is n the visible range of the buffer. */
if (pos < BEGV || pos > ZV)
  args_out_of_range (make_int (start), make_int (ZV));

Shouldn't the lower bound condition be pos < start instead of pos < BEGV?