make sure to include all relevant header files

Change-Id: I313d3a7dce5143ad8703e8ef8c2d066e652a4483
Reviewed-on: https://gerrit.libreoffice.org/43248
Reviewed-by: Markus Mohrhard <markus.mohrhard@googlemail.com>
Tested-by: Markus Mohrhard <markus.mohrhard@googlemail.com>
diff --git a/sc/source/ui/inc/output.hxx b/sc/source/ui/inc/output.hxx
index af50010..29c1526 100644
--- a/sc/source/ui/inc/output.hxx
+++ b/sc/source/ui/inc/output.hxx
@@ -26,6 +26,7 @@
#include <tools/fract.hxx>
#include <com/sun/star/embed/XEmbeddedObject.hpp>
#include <drawinglayer/processor2d/baseprocessor2d.hxx>
#include <editeng/svxenum.hxx>

namespace sc {
    struct SpellCheckContext;