some nits
https://codereview.appspot.com/557670043/diff/569610043/input/regression/system-start-brace-style.ly File input/regression/system-start-brace-style.ly (right): https://codereview.appspot.com/557670043/diff/569610043/input/regression/system-start-brace-style.ly#newcode4 input/regression/system-start-brace-style.ly:4: SystemStartGrob's style of @code{StaffGroup} to @code{'brace}, always prints a @code{SystemStart@var{Grob}} – and no comma after 'brace https://codereview.appspot.com/557670043/diff/569610043/input/regression/system-start-brace-style.ly#newcode6 input/regression/system-start-brace-style.ly:6: Every @code{StaffGroup} should start with a @code{SystemStartBrace}. If you want a new paragraph, please add an empty line before the sentence. https://codereview.appspot.com/557670043/diff/569610043/lily/system-start-delimiter.cc File lily/system-start-delimiter.cc (right): https://codereview.appspot.com/557670043/diff/569610043/lily/system-start-delimiter.cc#newcode151 lily/system-start-delimiter.cc:151: esp. because that triggers mktextfm for non-existent mktextfm is no longer relevant to LilyPond since we don't have a TeX back-end anymore. Maybe the comment should be just We use the style sheet to look up the font file name. This is better than using 'find_font' directly. https://codereview.appspot.com/557670043/
