SPIGOT-4339: Add EntityTransformEvent

Thanks klugemonkey for some contributions in https://hub.spigotmc.org/stash/projects/SPIGOT/repos/bukkit/pull-requests/351/overview

nms-patches/EntityZombieVillager.patch

@@ -1,6 +1,17 @@
 --- a/net/minecraft/server/EntityZombieVillager.java
 +++ b/net/minecraft/server/EntityZombieVillager.java
-@@ -9,6 +9,7 @@
+@@ -2,6 +2,10 @@
+ 
+ import java.util.UUID;
+ import javax.annotation.Nullable;
++// CraftBukkit start
++import org.bukkit.craftbukkit.event.CraftEventFactory;
++import org.bukkit.event.entity.EntityTransformEvent;
++// CraftBukkit end
+ 
+ public class EntityZombieVillager extends EntityZombie {
+ 
+@@ -9,6 +13,7 @@
      private static final DataWatcherObject<Integer> b = DataWatcher.a(EntityZombieVillager.class, DataWatcherRegistry.b);
      private int conversionTime;
      private UUID bD;
@@ -8,7 +19,7 @@
  
      public EntityZombieVillager(World world) {
          super(EntityTypes.ZOMBIE_VILLAGER, world);
-@@ -54,8 +55,13 @@
+@@ -54,8 +59,13 @@
      }
  
      public void tick() {
@@ -23,7 +34,7 @@
  
              this.conversionTime -= i;
              if (this.conversionTime <= 0) {
-@@ -100,8 +106,10 @@
+@@ -100,8 +110,10 @@
          this.bD = uuid;
          this.conversionTime = i;
          this.getDataWatcher().set(EntityZombieVillager.a, Boolean.valueOf(true));
@@ -36,16 +47,21 @@
          this.world.broadcastEntityEffect(this, (byte) 16);
      }
  
-@@ -123,7 +131,7 @@
+@@ -123,7 +135,12 @@
              entityvillager.setCustomNameVisible(this.getCustomNameVisible());
          }
  
 -        this.world.addEntity(entityvillager);
++        // CraftBukkit start
++        if (CraftEventFactory.callEntityTransformEvent(this, entityvillager, EntityTransformEvent.TransformReason.CURED).isCancelled()) {
++            return;
++        }
++        // CraftBukkit end
 +        this.world.addEntity(entityvillager, org.bukkit.event.entity.CreatureSpawnEvent.SpawnReason.CURED); // CraftBukkit - add SpawnReason
          if (this.bD != null) {
              EntityHuman entityhuman = this.world.b(this.bD);
  
-@@ -132,7 +140,7 @@
+@@ -132,7 +149,7 @@
              }
          }