Issue #124, case 1: Added test for this case
Actual fix is in stx:libbasic, revision 3563e89f551b.
https://swing.fit.cvut.cz/projects/stx-jv/ticket/124#comment:19
#define ScrollDn_width 14
#define ScrollDn_height 14
static unsigned char ScrollDn_bits[] = {
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x06, 0x18, 0x0e, 0x1c,
0x1c, 0x0e, 0x38, 0x07, 0xf0, 0x03, 0xe0, 0x01, 0xc0, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00};