Fixed some mixins crash

src/main/java/com/minelittlepony/client/ducks/IRenderItem.java

@@ -6,4 +6,9 @@ public interface IRenderItem {
      * Sets whether items should be rendered with transparency support.
      */
     void useTransparency(boolean use);
+
+    /**
+     * Returns true if this renderer is set to render models as a transparent overlay.
+     */
+    boolean usesTransparency();
 }

src/main/java/com/minelittlepony/client/mixin/MixinItemRenderer.java

@@ -34,6 +34,21 @@ public abstract class MixinItemRenderer implements SynchronousResourceReloadList
         }
     }
 
+    @Inject(method = "renderItemAndGlow("
+            + "Lnet/minecraft/item/ItemStack;"
+            + "Lnet/minecraft/client/render/model/BakedModel;)V",
+            at = @At(value = "INVOKE",
+                    target = "Lnet/minecraft/client/render/item/ItemRenderer;renderGlint("
+                            + "Lnet/minecraft/client/texture/TextureManager;"
+                            + "Ljava/lang/Runnable;I)V"),
+            cancellable = true)
+    private void beforeRenderEffect(ItemStack stack, BakedModel model, CallbackInfo info) {
+        if (transparency) {
+            info.cancel();
+        }
+    }
+
+
     @ModifyArg(method = "renderQuads("
             + "Lnet/minecraft/client/render/BufferBuilder;"
             + "Ljava/util/List;I"
@@ -46,14 +61,4 @@ public abstract class MixinItemRenderer implements SynchronousResourceReloadList
     private int modifyItemRenderTint(int color) {
         return transparency ? -1 : color;
     }
-
-    @Inject(method = "renderEffect("
-            + "Lnet/minecraft/client/render/model/BakedModel;)V",
-            at = @At("HEAD"),
-            cancellable = true)
-    private void renderEffect(BakedModel model, CallbackInfo info) {
-        if (transparency) {
-            info.cancel();
-        }
-    }
 }

src/main/java/com/minelittlepony/client/render/tileentities/skull/PonySkullRenderer.java

@@ -148,6 +148,7 @@ public class PonySkullRenderer extends SkullBlockEntityRenderer implements IRend
         transparency = use;
     }
 
+    @Override
     public boolean usesTransparency() {
         return transparency;
     }