[LyX/master] Add class attribute for \mathbb in XHTML output.

[Richard Heck]

commit e3625b5b8052e75e8741152bdfd313b54969c675
Author: Richard Heck <rgh...@lyx.org>
Date:   Wed Jun 29 22:47:21 2016 -0400

    Add class attribute for \mathbb in XHTML output.
    
    Patch from Josh.
---
 src/mathed/InsetMathFont.cpp |   12 +++++++++---
 1 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/src/mathed/InsetMathFont.cpp b/src/mathed/InsetMathFont.cpp
index b7b3dfb..020509d 100644
--- a/src/mathed/InsetMathFont.cpp
+++ b/src/mathed/InsetMathFont.cpp
@@ -203,9 +203,15 @@ void InsetMathFont::mathmlize(MathStream & os) const
        // no support at present for textipa, textsc, noun
 
        if (!variant.empty()) {
-               os << MTag("mstyle", "mathvariant='" + variant + "'")
-                  << cell(0)
-                  << ETag("mstyle");
+               if (tag == "mathbb") {
+                       os << MTag("mstyle", "class='mathbb' mathvariant='" + 
variant + "'")
+                          << cell(0)
+                          << ETag("mstyle");
+               } else {
+                       os << MTag("mstyle", "mathvariant='" + variant + "'")
+                                << cell(0)
+                                << ETag("mstyle");
+               }
        } else
                os << cell(0);
 }