TextEditor: Hide part of OutlineFactory implementation

Change-Id: Ifb1c743ba53e2e55605b78336b57c993c12ead3e
Reviewed-by: David Schulz <david.schulz@qt.io>

src/plugins/texteditor/texteditorplugin.cpp

@@ -43,6 +43,8 @@
 #include <utils/qtcassert.h>
 #include <utils/macroexpander.h>
 
+#include <QMenu>
+
 using namespace Core;
 using namespace Utils;