-Werror,-Wdelete-non-virtual-dtor

"thumbviewer.cxx(168,9) :  error: delete called on 'StreamOnZipBuffer' that has
virtual functions but non-virtual destructor"

Change-Id: I34510d54b9a99d8f1f9e8da0236625023c3fd94c

shell/source/win32/shlxthandler/thumbviewer/thumbviewer.cxx

@@ -117,7 +117,7 @@ namespace internal
     }
 }
 
-class StreamOnZipBuffer : public IStream
+class StreamOnZipBuffer final : public IStream
 {
 public:
     StreamOnZipBuffer(const ZipFile::ZipContentBuffer_t& zip_buffer);