[longomatch] Handle correctly empty ROI's in the drawing tool

[Andoni Morales Alastruey <amorales src gnome org>]

commit 8c1e89d50fb57e25a88696d833f047d05df2f1a9
Author: Andoni Morales Alastruey <ylatuya gmail com>
Date:   Mon Apr 27 19:07:49 2015 +0200

    Handle correctly empty ROI's in the drawing tool

 LongoMatch.GUI/Gui/Dialog/DrawingTool.cs |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)
---
diff --git a/LongoMatch.GUI/Gui/Dialog/DrawingTool.cs b/LongoMatch.GUI/Gui/Dialog/DrawingTool.cs
index f88457e..81f42da 100644
--- a/LongoMatch.GUI/Gui/Dialog/DrawingTool.cs
+++ b/LongoMatch.GUI/Gui/Dialog/DrawingTool.cs
@@ -545,7 +545,8 @@ namespace LongoMatch.Gui.Dialog
 
                void HandleRegionOfInterestChanged (object sender, EventArgs e)
                {
-                       if (blackboard.RegionOfInterest.Width == blackboard.Background.Width &&
+                       if (blackboard.RegionOfInterest.Empty ||
+                           blackboard.RegionOfInterest.Width == blackboard.Background.Width &&
                            blackboard.RegionOfInterest.Height == blackboard.Background.Height) {
                                hscrollbar.Visible = false;
                                wscrollbar.Visible = false;