Actually push the CraftOfflinePlayer implementation!

src/main/java/org/bukkit/craftbukkit/CraftOfflinePlayer.java

@@ -0,0 +1,40 @@
+package org.bukkit.craftbukkit;
+
+import org.bukkit.OfflinePlayer;
+import org.bukkit.Server;
+
+public class CraftOfflinePlayer implements OfflinePlayer {
+    private final String name;
+    private final CraftServer server;
+
+    protected CraftOfflinePlayer(CraftServer server, String name) {
+        this.server = server;
+        this.name = name;
+    }
+
+    public boolean isOnline() {
+        return false;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public Server getServer() {
+        return server;
+    }
+
+    public boolean isOp() {
+        return server.getHandle().isOp(getName());
+    }
+
+    public void setOp(boolean value) {
+        if (value == isOp()) return;
+
+        if (value) {
+            server.getHandle().e(getName());
+        } else {
+            server.getHandle().f(getName());
+        }
+    }
+}