Issues warning for empty note column extents (issue 6499105)

[k-ohara5a5a]

LGTM


http://codereview.appspot.com/6499105/diff/1/lily/stem.cc
File lily/stem.cc (left):

http://codereview.appspot.com/6499105/diff/1/lily/stem.cc#oldcode814
lily/stem.cc:814: if (lh && robust_scm2int (lh->get_property
("duration-log"), 0) < 1)
Removing this looks extremely sensible.

It does change the output from the bug report, though, relative to
version.  Now the stems and flags /are/ printed on the eight-notes,
despite their whole note heads.

The new behavior seems less surprising to me.  The bug reporter said he
will switch to the simpler c1*1/8 , so he will not be affected by the
change.

(If, perchance, we decide to retain the old behavior, it would of course
be much more clear to decide that such a stem is invisible in the
function is_invisible().)

http://codereview.appspot.com/6499105/