Fix entity motion tag from mob spawners (#5718)

Spigot-Server-Patches/0566-Fix-Entity-Teleportation-and-cancel-velocity-if-tele.patch

@@ -31,14 +31,14 @@ index 1d154ef60fd979340cf925748251669e860d4094..68f8a7f227c4d683d4c13d634ccfbabe
          this.player.playerConnection.sendPacket(new PacketPlayOutPosition(d0 - d3, d1 - d4, d2 - d5, f - f2, f1 - f3, set, this.teleportAwait));
      }
 diff --git a/src/main/java/net/minecraft/world/entity/Entity.java b/src/main/java/net/minecraft/world/entity/Entity.java
-index 743d4725c0a26a8abd0a98eed2ec45ffba6211ad..344862c3f479ae7b6d4f929c9ef7882aba983ffb 100644
+index 743d4725c0a26a8abd0a98eed2ec45ffba6211ad..58d9dce288ab9cc1989cfcb66703b76fdabf1319 100644
 --- a/src/main/java/net/minecraft/world/entity/Entity.java
 +++ b/src/main/java/net/minecraft/world/entity/Entity.java
 @@ -145,6 +145,7 @@ public abstract class Entity implements INamableTileEntity, ICommandListener, ne
  
      // CraftBukkit start
      private static final int CURRENT_LEVEL = 2;
-+    boolean preserveMotion = true; // Paper - keep initial motion on first setPositionRotation
++    public boolean preserveMotion = true; // Paper - keep initial motion on first setPositionRotation
      static boolean isLevelAtLeast(NBTTagCompound tag, int level) {
          return tag.hasKey("Bukkit.updateLevel") && tag.getInt("Bukkit.updateLevel") >= level;
      }
@@ -56,6 +56,18 @@ index 743d4725c0a26a8abd0a98eed2ec45ffba6211ad..344862c3f479ae7b6d4f929c9ef7882a
          this.g(d0, d1, d2);
          this.yaw = f;
          this.pitch = f1;
+diff --git a/src/main/java/net/minecraft/world/level/MobSpawnerAbstract.java b/src/main/java/net/minecraft/world/level/MobSpawnerAbstract.java
+index 5538404456dfee42257fad9040fcc0fefdfc5fab..33a5dbcc11455f81088d9fd685a8c4b1b8f4b1f2 100644
+--- a/src/main/java/net/minecraft/world/level/MobSpawnerAbstract.java
++++ b/src/main/java/net/minecraft/world/level/MobSpawnerAbstract.java
+@@ -165,6 +165,7 @@ public abstract class MobSpawnerAbstract {
+                                 return;
+                             }
+ 
++                            entity.preserveMotion = true; // Paper - preserve entity motion from tag
+                             entity.setPositionRotation(entity.locX(), entity.locY(), entity.locZ(), world.random.nextFloat() * 360.0F, 0.0F);
+                             if (entity instanceof EntityInsentient) {
+                                 EntityInsentient entityinsentient = (EntityInsentient) entity;
 diff --git a/src/main/java/org/bukkit/craftbukkit/entity/CraftEntity.java b/src/main/java/org/bukkit/craftbukkit/entity/CraftEntity.java
 index 387f6f6fa9bbb1cce544cfb907f68c7993752dd7..fb52a60437d48282f3e99e7eccb0e76b446155f9 100644
 --- a/src/main/java/org/bukkit/craftbukkit/entity/CraftEntity.java