[LyX/master] Fix silly error outputting math sizes. Fixes bug #10129.

[Richard Heck]

commit bb5c760b37cbc360a46c5cca83178c5b79c3b9b3
Author: Richard Heck <rgh...@lyx.org>
Date:   Sat Jun 11 00:48:55 2016 -0400

    Fix silly error outputting math sizes. Fixes bug #10129.

diff --git a/src/mathed/InsetMathSize.cpp b/src/mathed/InsetMathSize.cpp
index dc79652..fc7c7ba 100644
--- a/src/mathed/InsetMathSize.cpp
+++ b/src/mathed/InsetMathSize.cpp
@@ -83,8 +83,7 @@ void InsetMathSize::mathmlize(MathStream & ms) const
        stringstream attrs;
        attrs << "displaystyle='" << (dispstyle ? "true" : "false")
                << "' scriptlevel='" << scriptlevel << "'";
-       ms << MTag("mstyle", attrs.str()) << ">"
-          << cell(0) << ETag("mstyle");
+       ms << MTag("mstyle", attrs.str()) << cell(0) << ETag("mstyle");
 }