Get rid of the direct access abuse of FullFramePixelBuffer's data
diff --git a/common/rfb/PixelBuffer.h b/common/rfb/PixelBuffer.h
index bff2802..9423024 100644
--- a/common/rfb/PixelBuffer.h
+++ b/common/rfb/PixelBuffer.h
@@ -130,11 +130,10 @@
     //   pixel is the Pixel value to be used where mask_ is set
     void maskRect(const Rect& r, Pixel pixel, const void* mask_);
 
-    // *** Should this be visible?
-    rdr::U8* data;
-
   protected:
     FullFramePixelBuffer();
+
+    rdr::U8* data;
   };
 
   // -=- Managed pixel buffer class