Fix frame end task race condition in ScrollPanelWidget

OpenRA.Game/Primitives/ObservableDictionary.cs

@@ -33,19 +33,19 @@ namespace OpenRA.Primitives
 	{
 		protected IDictionary<TKey, TValue> innerDict;
 
-		public event Action<object> OnAdd = k => { };
-		public event Action<object> OnRemove = k => { };
+		public event Action<IObservableCollection, object> OnAdd = (x, k) => { };
+		public event Action<IObservableCollection, object> OnRemove = (x, k) => { };
 
 		// TODO Workaround for https://github.com/OpenRA/OpenRA/issues/6101
 		#pragma warning disable 67
-		public event Action<int> OnRemoveAt = i => { };
-		public event Action<object, object> OnSet = (o, n) => { };
+		public event Action<IObservableCollection, int> OnRemoveAt = (x, i) => { };
+		public event Action<IObservableCollection, object, object> OnSet = (x, o, n) => { };
 		#pragma warning restore
-		public event Action OnRefresh = () => { };
+		public event Action<IObservableCollection> OnRefresh = x => { };
 
 		protected void FireOnRefresh()
 		{
-			OnRefresh();
+			OnRefresh(this);
 		}
 
 		protected ObservableDictionary() { }
@@ -58,14 +58,14 @@ namespace OpenRA.Primitives
 		public virtual void Add(TKey key, TValue value)
 		{
 			innerDict.Add(key, value);
-			OnAdd(key);
+			OnAdd(this, key);
 		}
 
 		public bool Remove(TKey key)
 		{
 			var found = innerDict.Remove(key);
 			if (found)
-				OnRemove(key);
+				OnRemove(this, key);
 			return found;
 		}
 
@@ -91,7 +91,7 @@ namespace OpenRA.Primitives
 		public void Clear()
 		{
 			innerDict.Clear();
-			OnRefresh();
+			OnRefresh(this);
 		}
 
 		public int Count