[longomatch] Fix rendering text to surfaces

[Andoni Morales Alastruey <amorales src gnome org>]

commit 20f0ce24e343c9ee45c4175cbe66a1b39a951573
Author: Andoni Morales Alastruey <ylatuya gmail com>
Date:   Fri Aug 29 14:25:10 2014 +0200

    Fix rendering text to surfaces

 LongoMatch.Drawing.Cairo/CairoBackend.cs |    9 +++++++--
 1 files changed, 7 insertions(+), 2 deletions(-)
---
diff --git a/LongoMatch.Drawing.Cairo/CairoBackend.cs b/LongoMatch.Drawing.Cairo/CairoBackend.cs
index 6e11dae..51c6aa9 100644
--- a/LongoMatch.Drawing.Cairo/CairoBackend.cs
+++ b/LongoMatch.Drawing.Cairo/CairoBackend.cs
@@ -338,14 +338,19 @@ namespace LongoMatch.Drawing.Cairo
 
                public void DrawText (Point point, double width, double height, string text)
                {
-                       Layout layout;
+                       Layout layout = null;
                        Pango.Rectangle inkRect, logRect;
                        
                        if (text == null) {
                                return;
                        }
 
-                       layout = (context as CairoContext).PangoLayout;
+                       if (context is CairoContext) {
+                               layout = (context as CairoContext).PangoLayout;
+                       }
+                       if (layout == null) {
+                               layout = Pango.CairoHelper.CreateLayout (CContext);
+                       }
                        layout.FontDescription = FontDescription.FromString (
                                String.Format ("{0} {1}px", FontFamily, FontSize));
                        layout.FontDescription.Weight = fWeight;