Add OnPlayEnding to editor modules and windows

#3514

Source/Editor/Editor.cs

@@ -670,6 +670,8 @@ namespace FlaxEditor
         {
             FlaxEngine.Networking.NetworkManager.Stop(); // Shutdown any multiplayer from playmode
             PlayModeEnding?.Invoke();
+            for (int i = 0; i < _modules.Count; i++)
+                _modules[i].OnPlayEnding();
         }
 
         internal void OnPlayEnd()

Source/Editor/Modules/EditorModule.cs

@@ -76,6 +76,13 @@ namespace FlaxEditor.Modules
         {
         }
 
+        /// <summary>
+        /// Called when Editor will leave the play mode.
+        /// </summary>
+        public virtual void OnPlayEnding()
+        {
+        }
+
         /// <summary>
         /// Called when Editor leaves the play mode.
         /// </summary>

Source/Editor/Modules/WindowsModule.cs

@@ -1223,6 +1223,13 @@ namespace FlaxEditor.Modules
                 Windows[i].OnPlayBegin();
         }
 
+        /// <inheritdoc />
+        public override void OnPlayEnding()
+        {
+            for (int i = 0; i < Windows.Count; i++)
+                Windows[i].OnPlayEnding();
+        }
+
         /// <inheritdoc />
         public override void OnPlayEnd()
         {

Source/Editor/Windows/EditorWindow.cs

@@ -219,6 +219,13 @@ namespace FlaxEditor.Windows
         {
         }
 
+        /// <summary>
+        /// Called when Editor will leave the play mode.
+        /// </summary>
+        public virtual void OnPlayEnding()
+        {
+        }
+
         /// <summary>
         /// Called when Editor leaves the play mode.
         /// </summary>