[banshee] GStreamerSharp: convert some Monitor calls into a lock{} block

[Andrés Aragoneses <aaragoneses src gnome org>]

commit 4b22a04a10828773da5306befdda99809ef5b4c0
Author: Andrés G. Aragoneses <knocte gmail com>
Date:   Tue Oct 29 22:59:27 2013 +0100

    GStreamerSharp: convert some Monitor calls into a lock{} block
    
    There was some synchronization-related Monitor.{Enter|Exit} calls here,
    which can be translated to a lock(){} block, which is:
    
     - Better syntax, as it avoids the fact that you could forget the call
     to Monitor.Exit().
     - Better protection against exceptions, as the Monitor.Exit() call that
     is generated by the lock's syntactic sugar is inside a finally{} block.
    
    The original author of this code probably thought that it was better to
    use two Monitor.Exit() calls in order to exit the synchronized region as
    soon as possible, but using a return statement inside a lock{} block for
    bailing out early is also possible.

 .../Banshee.GStreamerSharp/VideoManager.cs         |   42 +++++++++----------
 1 files changed, 20 insertions(+), 22 deletions(-)
---
diff --git a/src/Backends/Banshee.GStreamerSharp/Banshee.GStreamerSharp/VideoManager.cs 
b/src/Backends/Banshee.GStreamerSharp/Banshee.GStreamerSharp/VideoManager.cs
index e44fd61..b6f7bc5 100644
--- a/src/Backends/Banshee.GStreamerSharp/Banshee.GStreamerSharp/VideoManager.cs
+++ b/src/Backends/Banshee.GStreamerSharp/Banshee.GStreamerSharp/VideoManager.cs
@@ -27,7 +27,6 @@
 //
 
 using System;
-using System.Threading;
 using System.Runtime.InteropServices;
 using Mono.Unix;
 
@@ -125,35 +124,34 @@ namespace Banshee.GStreamerSharp
 
             video_sink = playbin.VideoSink;
 
-            Monitor.Enter (video_mutex);
+            lock (video_mutex) {
 
-            if (video_sink == null) {
-                xoverlay = null;
-                Monitor.Exit (video_mutex);
-                return false;
-            }
+                if (video_sink == null) {
+                    xoverlay = null;
+                    return false;
+                }
 
-            xoverlay_element = video_sink is Bin
-                ? ((Bin)video_sink).GetByInterface (new XOverlayAdapter ().GType)
-                : video_sink;
+                xoverlay_element = video_sink is Bin
+                    ? ((Bin)video_sink).GetByInterface (new XOverlayAdapter ().GType)
+                    : video_sink;
 
-            xoverlay = new XOverlayAdapter (xoverlay_element.Handle);
+                xoverlay = new XOverlayAdapter (xoverlay_element.Handle);
 
-            if (!PlatformDetection.IsWindows) {
-                // We can't rely on aspect ratio from dshowvideosink
-                if (xoverlay != null && xoverlay_element.HasProperty ("force-aspect-ratio")) {
-                    xoverlay_element ["force-aspect-ratio"] = true;
+                if (!PlatformDetection.IsWindows) {
+                    // We can't rely on aspect ratio from dshowvideosink
+                    if (xoverlay != null && xoverlay_element.HasProperty ("force-aspect-ratio")) {
+                        xoverlay_element ["force-aspect-ratio"] = true;
+                    }
                 }
-            }
 
-            if (xoverlay != null && xoverlay_element.HasProperty ("handle-events")) {
-                xoverlay_element ["handle-events"] = false;
-            }
+                if (xoverlay != null && xoverlay_element.HasProperty ("handle-events")) {
+                    xoverlay_element ["handle-events"] = false;
+                }
 
-            found_xoverlay = (xoverlay != null) ? true : false;
+                found_xoverlay = (xoverlay != null) ? true : false;
 
-            Monitor.Exit (video_mutex);
-            return found_xoverlay;
+                return found_xoverlay;
+            }
         }
 
         public void ParseStreamInfo ()