[LyX/master] Remove unused variable warning

[Guillaume Munch]

commit 071eed8664d0f4372f0a10087ce73e80eb1d4fca
Author: Guillaume Munch <g...@lyx.org>
Date:   Sun Oct 9 19:47:50 2016 +0200

    Remove unused variable warning
---
 src/mathed/InsetMathGrid.cpp |    1 -
 1 files changed, 0 insertions(+), 1 deletions(-)

diff --git a/src/mathed/InsetMathGrid.cpp b/src/mathed/InsetMathGrid.cpp
index e7e20df..a0269c5 100644
--- a/src/mathed/InsetMathGrid.cpp
+++ b/src/mathed/InsetMathGrid.cpp
@@ -620,7 +620,6 @@ int InsetMathGrid::hLineVOffset(row_type row, unsigned int 
line) const
 
 void InsetMathGrid::draw(PainterInfo & pi, int x, int y) const
 {
-       Dimension const dim = dimension(*pi.base.bv);
        BufferView const & bv = *pi.base.bv;
 
        for (idx_type idx = 0; idx < nargs(); ++idx) {