Only add sorted/deduplicated mods to the classpath.

Fixes some mods causing the Forge error displays to break. Closes #9833

src/main/java/net/minecraftforge/client/ForgeHooksClient.java

@@ -469,7 +469,7 @@ public class ForgeHooksClient {
     // TODO Do we need this?
     public static void fillNormal(int[] faceData, Direction facing, boolean calculateNormals) {
         Vector3f v2;
-        if (calculateNormals || ForgeConfig.CLIENT.calculateAllNormals.get()) {
+        if (calculateNormals || ForgeConfig.CLIENT.calculateAllNormals()) {
             Vector3f v1 = getVertexPos(faceData, 3);
             Vector3f t1 = getVertexPos(faceData, 1);
             v2 = getVertexPos(faceData, 2);

src/main/java/net/minecraftforge/client/loading/ClientModLoader.java

@@ -5,24 +5,12 @@
 
 package net.minecraftforge.client.loading;
 
-
 import java.io.File;
-import java.util.ArrayList;
 import java.util.Collections;
-import java.util.Map;
-import java.util.Map.Entry;
-import java.util.Optional;
 import java.util.concurrent.*;
-import java.util.function.Consumer;
-
-import net.minecraft.network.chat.Component;
-import net.minecraft.server.packs.repository.RepositorySource;
-import net.minecraft.server.packs.repository.Pack.Info;
 import net.minecraft.server.packs.resources.PreparableReloadListener;
-import net.minecraft.server.packs.repository.PackSource;
 import net.minecraft.server.packs.resources.ReloadableResourceManager;
 import net.minecraft.server.packs.resources.ResourceManager;
-import net.minecraft.server.packs.repository.Pack;
 import net.minecraft.server.packs.repository.PackRepository;
 import net.minecraft.world.level.DataPackConfig;
 import net.minecraftforge.event.AddPackFindersEvent;
@@ -31,26 +19,19 @@ import net.minecraftforge.fml.loading.ImmediateWindowHandler;
 import net.minecraftforge.internal.BrandingControl;
 import net.minecraftforge.logging.CrashReportExtender;
 import net.minecraftforge.common.util.LogicalSidedProvider;
-import net.minecraftforge.forgespi.locating.IModFile;
-import net.minecraftforge.resource.PathPackResources;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 
-import net.minecraft.SharedConstants;
 import net.minecraft.client.Minecraft;
 import net.minecraft.util.profiling.ProfilerFiller;
-import net.minecraft.server.packs.PackResources;
 import net.minecraft.server.packs.PackType;
-import net.minecraft.server.packs.metadata.pack.PackMetadataSection;
 import net.minecraftforge.api.distmarker.Dist;
 import net.minecraftforge.api.distmarker.OnlyIn;
 import net.minecraftforge.common.ForgeConfig;
 import net.minecraftforge.common.MinecraftForge;
 import net.minecraftforge.client.gui.LoadingErrorScreen;
-import net.minecraftforge.resource.DelegatingPackResources;
 import net.minecraftforge.resource.ResourcePackLoader;
 import net.minecraftforge.server.LanguageHook;
-import net.minecraftforge.forgespi.language.IModInfo;
 
 @OnlyIn(Dist.CLIENT)
 public class ClientModLoader {
@@ -117,12 +98,7 @@ public class ClientModLoader {
 
     public static boolean completeModLoading() {
         var warnings = ModLoader.get().getWarnings();
-        boolean showWarnings = true;
-        try {
-            showWarnings = ForgeConfig.CLIENT.showLoadWarnings.get();
-        } catch (NullPointerException | IllegalStateException e) {
-            // We're in an early error state, config is not available. Assume true.
-        }
+        boolean showWarnings = ForgeConfig.CLIENT.showLoadWarnings();
 
         if (!showWarnings) {
             //User disabled warning screen, as least log them

src/main/java/net/minecraftforge/common/ForgeConfig.java

@@ -158,6 +158,16 @@ public class ForgeConfig {
 
             builder.pop();
         }
+
+        // Allow these to be called before the config is loaded because its used before loading the error screens.
+        // Prevents a ton of spam when an error screen is displayed.
+        public final boolean calculateAllNormals() {
+            return clientSpec.isLoaded() ? calculateAllNormals.get() : calculateAllNormals.getDefault();
+        }
+
+        public final boolean showLoadWarnings() {
+            return clientSpec.isLoaded() ? showLoadWarnings.get() : showLoadWarnings.getDefault();
+        }
     }
 
     static final ForgeConfigSpec clientSpec;