[LyX/master] Toggle properly the math-display icon

[Jean-Marc Lasgouttes]

commit af4548cd6b40b7eb6478535b422b1bc4c33182cd
Author: Jean-Marc Lasgouttes <lasgout...@lyx.org>
Date:   Thu Apr 16 18:51:29 2015 +0200

    Toggle properly the math-display icon

diff --git a/src/mathed/InsetMathHull.cpp b/src/mathed/InsetMathHull.cpp
index 53a16e8..b9c5b2c 100644
--- a/src/mathed/InsetMathHull.cpp
+++ b/src/mathed/InsetMathHull.cpp
@@ -1645,6 +1645,7 @@ bool InsetMathHull::getStatus(Cursor & cur, FuncRequest 
const & cmd,
                                enable = display() != Inline;
                }
                status.setEnabled(enable);
+               status.setOnOff(display() != Inline);
                return true;
        }