SPIGOT-3553: Add OfflinePlayer based methods to SkullMeta

By: md_5 <git@md-5.net>

paper-api/src/main/java/org/bukkit/inventory/meta/SkullMeta.java

@@ -1,6 +1,7 @@
 package org.bukkit.inventory.meta;
 
 import org.bukkit.Material;
+import org.bukkit.OfflinePlayer;
 
 /**
  * Represents a skull ({@link Material#SKULL_ITEM}) that can have an owner.
@@ -11,7 +12,9 @@ public interface SkullMeta extends ItemMeta {
      * Gets the owner of the skull.
      *
      * @return the owner if the skull
+     * @deprecated see {@link #setOwningPlayer(org.bukkit.OfflinePlayer)}.
      */
+    @Deprecated
     String getOwner();
 
     /**
@@ -29,8 +32,28 @@ public interface SkullMeta extends ItemMeta {
      *
      * @param owner the new owner of the skull
      * @return true if the owner was successfully set
+     * @deprecated see {@link #setOwningPlayer(org.bukkit.OfflinePlayer)}.
      */
+    @Deprecated
     boolean setOwner(String owner);
 
+    /**
+     * Gets the owner of the skull.
+     *
+     * @return the owner if the skull
+     */
+    OfflinePlayer getOwningPlayer();
+
+    /**
+     * Sets the owner of the skull.
+     * <p>
+     * Plugins should check that hasOwner() returns true before calling this
+     * plugin.
+     *
+     * @param owner the new owner of the skull
+     * @return true if the owner was successfully set
+     */
+    boolean setOwningPlayer(OfflinePlayer owner);
+
     SkullMeta clone();
 }