Change the way initial state saving works in EditorChangeHandler to be closer to first change

osu.Game/Screens/Edit/BeatmapEditorChangeHandler.cs

@@ -26,9 +26,6 @@ namespace osu.Game.Screens.Edit
             editorBeatmap.SaveStateTriggered += SaveState;
 
             patcher = new LegacyEditorBeatmapPatcher(editorBeatmap);
-
-            // Initial state.
-            SaveState();
         }
 
         protected override void WriteCurrentStateToStream(MemoryStream stream)

osu.Game/Screens/Edit/EditorChangeHandler.cs

@@ -31,6 +31,8 @@ namespace osu.Game.Screens.Edit
         {
             get
             {
+                ensureStateSaved();
+
                 using (var stream = new MemoryStream(savedStates[currentState]))
                     return stream.ComputeSHA2Hash();
             }
@@ -40,6 +42,19 @@ namespace osu.Game.Screens.Edit
 
         public const int MAX_SAVED_STATES = 50;
 
+        public override void BeginChange()
+        {
+            ensureStateSaved();
+
+            base.BeginChange();
+        }
+
+        private void ensureStateSaved()
+        {
+            if (savedStates.Count == 0)
+                SaveState();
+        }
+
         protected override void UpdateState()
         {
             if (isRestoring)

osu.Game/Screens/Edit/TransactionalCommitComponent.cs

@@ -33,7 +33,7 @@ namespace osu.Game.Screens.Edit
         /// <summary>
         /// Signal the beginning of a change.
         /// </summary>
-        public void BeginChange()
+        public virtual void BeginChange()
         {
             if (bulkChangesStarted++ == 0)
                 TransactionBegan?.Invoke();