[f-spot] no longer crash on dst changes

[Stephane Delcroix <sdelcroix src gnome org>]

commit 45fe9d3d18ea5632ec973c94642263e94e375e73
Author: Stephane Delcroix <stephane delcroix org>
Date:   Mon Jul 13 12:09:29 2009 +0200

    no longer crash on dst changes
    
    this fix for bgo#588361 workaround what I think it's a bug in mono dto implementation of +=

 src/Widgets/DateEdit.cs |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/src/Widgets/DateEdit.cs b/src/Widgets/DateEdit.cs
index 96bfd6d..e46ca3c 100644
--- a/src/Widgets/DateEdit.cs
+++ b/src/Widgets/DateEdit.cs
@@ -213,7 +213,7 @@ namespace FSpot.Widgets
 		{
 			DateTimeOffset new_date;
 			if (DateTimeOffset.TryParseExact (date_entry.Text, "d", null, System.Globalization.DateTimeStyles.AssumeLocal | System.Globalization.DateTimeStyles.AllowWhiteSpaces, out new_date))
-				DateTimeOffset += (new_date.Date - DateTimeOffset.Date);
+				DateTimeOffset = new DateTimeOffset (calendar.Date + DateTimeOffset.TimeOfDay, DateTimeOffset.Offset);
 			else 
 				date_entry.ModifyBase (StateType.Normal, red);
 		}
@@ -245,7 +245,7 @@ namespace FSpot.Widgets
 
 		void HandleCalendarDaySelected (object sender, EventArgs e)
 		{
-			DateTimeOffset += (calendar.Date - DateTimeOffset.Date);
+			DateTimeOffset = new DateTimeOffset (calendar.Date + DateTimeOffset.TimeOfDay, DateTimeOffset.Offset);
 		}
 
 		void HandleCalendarDaySelectedDoubleClick (object sender, EventArgs e)