Improve make-bracket-bar-line (issue 339670043 by address@hidden)

[thomasmorley65]

Reviewers: ,

Description:
Improve make-bracket-bar-line

The previously used ly:stencil-scale -1 1 resulted in wrongly positioned
SpanBars in certain cases.
Replaces ly:stencil-scale by flip-stencil.

Please review this at https://codereview.appspot.com/339670043/

Affected files (+1, -1 lines):
  M scm/bar-line.scm


Index: scm/bar-line.scm
diff --git a/scm/bar-line.scm b/scm/bar-line.scm
index  
3fad8f8912949bf96a9944b6a1019432be850cb3..0f204547dfa473aaae02132d0a1e1853d3d18b76  
100644
--- a/scm/bar-line.scm
+++ b/scm/bar-line.scm
@@ -514,7 +514,7 @@ opening bracket will be drawn, for @code{RIGHT} we get  
the closing bracket."

     (if (eqv? dir LEFT)
         stencil
-        (ly:stencil-scale stencil -1 1))))
+        (flip-stencil X stencil))))

 (define ((make-spacer-bar-line glyph) grob extent)
   "Draw an invisible bar line which has the same dimensions as the one