Add method to IResourcePack to hide it entirely from the UI (#5525)

src/main/java/net/minecraftforge/client/extensions/IForgeResourcePack.java

@@ -0,0 +1,28 @@
+/*
+ * Minecraft Forge
+ * Copyright (c) 2016-2019.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation version 2.1
+ * of the License.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+package net.minecraftforge.client.extensions;
+
+public interface IForgeResourcePack
+{
+    default boolean isHidden()
+    {
+        return false;
+    }
+}

src/main/java/net/minecraftforge/fml/packs/ModFileResourcePack.java

@@ -218,4 +218,9 @@ public class ModFileResourcePack extends AbstractResourcePack
     <T extends ResourcePackInfo> T getPackInfo() {
         return (T)this.packInfo;
     }
+    
+    @Override
+    public boolean isHidden() {
+    	return !modFile.getModFileInfo().showAsResourcePack();
+    }
 }