Fix inability to attack while holding modifier keys

src/main/java/net/minecraftforge/client/settings/KeyBindingMap.java

@@ -22,7 +22,17 @@ public class KeyBindingMap
     public KeyBinding lookupActive(int keyCode)
     {
         KeyModifier activeModifier = KeyModifier.isKeyCodeModifier(keyCode) ? KeyModifier.NONE : KeyModifier.getActiveModifier();
-        Collection<KeyBinding> bindings = map.get(activeModifier).lookup(keyCode);
+        KeyBinding binding = getBinding(keyCode, activeModifier);
+        if (binding != null)
+        {
+            return binding;
+        }
+        return getBinding(keyCode, KeyModifier.NOT_SUPPORTED);
+    }
+
+    private KeyBinding getBinding(int keyCode, KeyModifier keyModifier)
+    {
+        Collection<KeyBinding> bindings = map.get(keyModifier).lookup(keyCode);
         if (bindings != null)
         {
             for (KeyBinding binding : bindings)

src/main/java/net/minecraftforge/client/settings/KeyModifier.java

@@ -83,6 +83,25 @@ public enum KeyModifier {
             return !SHIFT.isActive()  && !CONTROL.isActive() && !ALT.isActive();
         }
 
+        @Override
+        public String getLocalizedComboName(String keyName)
+        {
+            return keyName;
+        }
+    },
+    NOT_SUPPORTED {
+        @Override
+        protected boolean matches(int keyCode)
+        {
+            return true;
+        }
+
+        @Override
+        public boolean isActive()
+        {
+            return true;
+        }
+
         @Override
         public String getLocalizedComboName(String keyName)
         {