handle textures whose assets no longer exist during asset propagation

Textures are reloaded in-place in Stardew Valley 1.6. That's much more efficient than the previous approach, but SMAPI can't take the game context into account anymore during asset propagation. That means textures which SMAPI would previously skip are now reloaded and may fail. For example, custom NPCs still exist in-memory when you return to title (since the game state isn't cleared yet), but often the mods which provide their portraits/sprites have unloaded their patches (e.g. because they depend on in-save Content Patcher tokens).

This commit mitigates that by logging a small warning when it happens, instead of the giant exception trace it logs otherwise.

Author: Pathoschild

src/SMAPI/Metadata/CoreAssetPropagator.cs

@@ -167,9 +167,18 @@ private bool PropagateTexture(IAssetName assetName, LocalizedContentManager.Lang
                 {
                     if (contentManager.IsLoaded(assetName))
                     {
-                        changed = true;
-                        Texture2D texture = contentManager.LoadLocalized<Texture2D>(assetName, language, useCache: true);
-                        texture.CopyFromTexture(newTexture.Value);
+                        if (this.DisposableContentManager.DoesAssetExist<Texture2D>(assetName))
+                        {
+                            changed = true;
+
+                            Texture2D texture = contentManager.LoadLocalized<Texture2D>(assetName, language, useCache: true);
+                            texture.CopyFromTexture(newTexture.Value);
+                        }
+                        else
+                        {
+                            this.Monitor.Log($"Skipped reload for '{assetName.Name}' because the underlying asset no longer exists.", LogLevel.Warn);
+                            break;
+                        }
                     }
                 }