Added code to debug disposables

src/Perspex.Base/PerspexDisposable.cs

@@ -3,23 +3,37 @@ using System.Collections.Generic;
 using System.Linq;
 using System.Text;
 using System.Threading.Tasks;
+using Perspex.Platform;
 
 namespace Perspex
 {
     public abstract class PerspexDisposable : IDisposable
     {
+#if DEBUG_DISPOSE
+        public string DisposedAt { get; private set; }
+#endif
+
+
         public bool IsDisposed { get; private set; }
 
         public void Dispose()
         {
             IsDisposed = true;
+#if DEBUG_DISPOSE
+            DisposedAt = PerspexLocator.Current.GetService<IPclPlatformWrapper>().GetStackTrace();
+#endif
             DoDispose();
         }
 
         protected void CheckDisposed()
         {
             if (IsDisposed)
-                throw new ObjectDisposedException(GetType().FullName);
+                throw new ObjectDisposedException(GetType().FullName
+#if DEBUG_DISPOSE
+                    , "Disposed at: \n" + DisposedAt
+#endif
+
+                    );
         }
 
         protected abstract void DoDispose();

src/Perspex.Base/Platform/IPclPlatformWrapper.cs

@@ -12,5 +12,6 @@ namespace Perspex.Platform
         Assembly[] GetLoadedAssemblies();
         void PostThreadPoolItem(Action cb);
         IDisposable StartSystemTimer(TimeSpan interval, Action tick);
+        string GetStackTrace();
     }
 }