try to avoid album year of zero

MediaBrowser.Controller/Drawing/IImageProcessor.cs

@@ -68,7 +68,7 @@ namespace MediaBrowser.Controller.Drawing
         /// <param name="imageEnhancers">The image enhancers.</param>
         /// <returns>Guid.</returns>
         Guid GetImageCacheTag(BaseItem item, ImageType imageType, string originalImagePath, DateTime dateModified,
-                              IEnumerable<IImageEnhancer> imageEnhancers);
+                              List<IImageEnhancer> imageEnhancers);
 
         /// <summary>
         /// Processes the image.

MediaBrowser.Providers/Music/LastfmHelper.cs

@@ -25,8 +25,13 @@ namespace MediaBrowser.Providers.Music
                 }
             }
 
-            artist.PremiereDate = yearFormed > 0 ? new DateTime(yearFormed, 1, 1, 0, 0, 0, DateTimeKind.Utc) : (DateTime?)null;
+            if (yearFormed > 0)
+            {
+                artist.PremiereDate = new DateTime(yearFormed, 1, 1, 0, 0, 0, DateTimeKind.Utc);
+
                 artist.ProductionYear = yearFormed;
+            }
+            
             if (data.tags != null && !artist.LockedFields.Contains(MetadataFields.Tags))
             {
                 AddTags(artist, data.tags);
@@ -102,11 +107,15 @@ namespace MediaBrowser.Providers.Music
 
             DateTime release;
 
-            if (DateTime.TryParse(data.releasedate, out release) && release.Year != 1901)
+            if (DateTime.TryParse(data.releasedate, out release))
+            {
+                // Lastfm sends back null as sometimes 1901, other times 0
+                if (release.Year > 1901)
                 {
                     item.PremiereDate = release;
                     item.ProductionYear = release.Year;
                 }
+            }
 
             if (data.toptags != null && !item.LockedFields.Contains(MetadataFields.Tags))
             {

MediaBrowser.Server.Implementations/Drawing/ImageProcessor.cs

@@ -589,7 +589,7 @@ namespace MediaBrowser.Server.Implementations.Drawing
 
             var supportedEnhancers = GetSupportedEnhancers(item, imageType);
 
-            return GetImageCacheTag(item, imageType, imagePath, dateModified, supportedEnhancers);
+            return GetImageCacheTag(item, imageType, imagePath, dateModified, supportedEnhancers.ToList());
         }
 
         /// <summary>
@@ -602,7 +602,7 @@ namespace MediaBrowser.Server.Implementations.Drawing
         /// <param name="imageEnhancers">The image enhancers.</param>
         /// <returns>Guid.</returns>
         /// <exception cref="System.ArgumentNullException">item</exception>
-        public Guid GetImageCacheTag(BaseItem item, ImageType imageType, string originalImagePath, DateTime dateModified, IEnumerable<IImageEnhancer> imageEnhancers)
+        public Guid GetImageCacheTag(BaseItem item, ImageType imageType, string originalImagePath, DateTime dateModified, List<IImageEnhancer> imageEnhancers)
         {
             if (item == null)
             {
@@ -619,6 +619,12 @@ namespace MediaBrowser.Server.Implementations.Drawing
                 throw new ArgumentNullException("originalImagePath");
             }
 
+            // Optimization
+            if (imageEnhancers.Count == 0)
+            {
+                return (originalImagePath + dateModified.Ticks).GetMD5();
+            }
+
             // Cache name is created with supported enhancers combined with the last config change so we pick up new config changes
             var cacheKeys = imageEnhancers.Select(i => i.GetConfigurationCacheKey(item, imageType)).ToList();
             cacheKeys.Add(originalImagePath + dateModified.Ticks);
@@ -879,7 +885,7 @@ namespace MediaBrowser.Server.Implementations.Drawing
             {
                 try
                 {
-                    return i.Supports(item as BaseItem, imageType);
+                    return i.Supports(item, imageType);
                 }
                 catch (Exception ex)
                 {
@@ -888,7 +894,7 @@ namespace MediaBrowser.Server.Implementations.Drawing
                     return false;
                 }
 
-            }).ToList();
+            });
         }
 
         public void Dispose()