Fix NPE for color-related metas

Fixes #10789

patches/server/General-ItemMeta-fixes.patch

@@ -586,6 +586,15 @@ index 0000000000000000000000000000000000000000..00000000000000000000000000000000
      }
  
      @Override
+@@ -0,0 +0,0 @@ public class CraftMetaColorableArmor extends CraftMetaArmor implements Colorable
+         if (meta instanceof CraftMetaColorableArmor) {
+             CraftMetaColorableArmor that = (CraftMetaColorableArmor) meta;
+ 
+-            return this.color.equals(that.color);
++            return this.hasColor() ? that.hasColor() && this.color.equals(that.color) : !that.hasColor(); // Paper - allow null
+         }
+         return true;
+     }
 diff --git a/src/main/java/org/bukkit/craftbukkit/inventory/CraftMetaCompass.java b/src/main/java/org/bukkit/craftbukkit/inventory/CraftMetaCompass.java
 index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
 --- a/src/main/java/org/bukkit/craftbukkit/inventory/CraftMetaCompass.java
@@ -1163,6 +1172,15 @@ index 0000000000000000000000000000000000000000..00000000000000000000000000000000
      }
  
      @Override
+@@ -0,0 +0,0 @@ class CraftMetaLeatherArmor extends CraftMetaItem implements LeatherArmorMeta {
+         if (meta instanceof CraftMetaLeatherArmor) {
+             CraftMetaLeatherArmor that = (CraftMetaLeatherArmor) meta;
+ 
+-            return this.color.equals(that.color);
++            return this.hasColor() ? that.hasColor() && this.color.equals(that.color) : !that.hasColor(); // Paper - allow null
+         }
+         return true;
+     }
 @@ -0,0 +0,0 @@ class CraftMetaLeatherArmor extends CraftMetaItem implements LeatherArmorMeta {
          return original != hash ? CraftMetaLeatherArmor.class.hashCode() ^ hash : hash;
      }