Allows user to set ChordName text (issue 6496085)

[dak]

http://codereview.appspot.com/6496085/diff/1/lily/chord-name-engraver.cc
File lily/chord-name-engraver.cc (right):

http://codereview.appspot.com/6496085/diff/1/lily/chord-name-engraver.cc#newcode83
lily/chord-name-engraver.cc:83: || ly_is_procedure
(chord_name_->get_property ("text")));
If it is a procedure, shouldn't it be called with the calculated value?

http://codereview.appspot.com/6496085/diff/1/lily/chord-name-engraver.cc#newcode87
lily/chord-name-engraver.cc:87: {
What kind of contorted logic and guessing game is that?
if (make_markup)
{
   [old code ending in setting "text"]
}

Please don't obfuscate code just to save reindentation.

http://codereview.appspot.com/6496085/diff/1/lily/chord-name-engraver.cc#newcode136
lily/chord-name-engraver.cc:136: markup = scm_call_4 (name_proc,
pitches, bass, inversion,
You do all the calculation and then throw it away?  Where is the point?

http://codereview.appspot.com/6496085/diff/1/lily/chord-name-engraver.cc#newcode149
lily/chord-name-engraver.cc:149: && ly_is_equal (chord_as_scm,
last_chord_))
If one is doing the chord calculation manually, you can't make the
decision of whether a chord changed based on the automatic calculation.
For better or worse, you need to compare the computed chord
versions/text.

http://codereview.appspot.com/6496085/