Replace spigot check with generation check

Author: lynxplay

paper-server/patches/sources/net/minecraft/server/level/ServerLevel.java.patch

@@ -1065,11 +1065,10 @@
      @Override
      public CrashReportCategory fillReportDetails(CrashReport report) {
          CrashReportCategory crashReportCategory = super.fillReportDetails(report);
-@@ -1712,6 +_,8 @@
+@@ -1712,6 +_,7 @@
      final class EntityCallbacks implements LevelCallback<Entity> {
          @Override
          public void onCreated(Entity entity) {
-+            entity.inWorld = true; // CraftBukkit - Mark entity as in world
 +            entity.setOldPosAndRot(); // Paper - update old pos / rot for new entities as it will default to Vec3.ZERO
          }
 
@@ -1109,10 +1108,11 @@
                      String string = "onTrackingStart called during navigation iteration";
                      Util.logAndPauseIfInIde(
                          "onTrackingStart called during navigation iteration", new IllegalStateException("onTrackingStart called during navigation iteration")
-@@ -1755,10 +_,51 @@
+@@ -1755,10 +_,52 @@
              }
 
              entity.updateDynamicGameEventListener(DynamicGameEventListener::add);
++            entity.inWorld = true; // CraftBukkit - Mark entity as in world
 +            entity.valid = true; // CraftBukkit
 +            ServerLevel.this.getChunkSource().addEntity(entity); // Paper - ignore and warn about illegal addEntity calls instead of crashing server
 +            // Paper start - Entity origin API

paper-server/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java

@@ -1961,10 +1961,8 @@ public static void callEntityRemoveEvent(Entity entity, EntityRemoveEvent.Cause
             return;
         }
 
-        // SPIGOT-8041: Do not call event unless entity has been spawned into world
-        if (!entity.inWorld) {
-            return;
-        }
+        // Do not call during generation.
+        if (entity.generation) return;
 
         Bukkit.getPluginManager().callEvent(new EntityRemoveEvent(entity.getBukkitEntity(), cause));
     }