block ocText for calc's threading

It may end up calling XColorList::CreateStdColorList(), and
XPropertyList is not thread-safe (gnome#627759-1 with disabled
mnOpenCLMinimumFormulaGroupSize).

Change-Id: I79c8335c6e8e3aaf39e01c68e6dbf6011820971a

sc/source/core/tool/token.cxx

@@ -1322,6 +1322,7 @@ void ScTokenArray::CheckForThreading( const FormulaToken& r )
         ocInfo,
         ocStyle,
         ocDBSum,
+        ocText,
         ocExternal,
         ocDde,
         ocWebservice,