Removed LegacyPluginPermissionsResolver.

Wrapping at the PermissionsProvider level instead, which removes some code duplication and fixes 2 warnings :)

src/main/java/com/sk89q/wepif/LegacyPermissionsProviderWrapper.java

@@ -0,0 +1,62 @@
+package com.sk89q.wepif;
+
+import org.bukkit.OfflinePlayer;
+import org.bukkit.plugin.Plugin;
+
+@SuppressWarnings("deprecation")
+public class LegacyPermissionsProviderWrapper implements PermissionsProvider {
+    private final com.sk89q.bukkit.migration.PermissionsProvider legacyPermissionsProvider;
+
+    static PermissionsProvider wrap(Plugin plugin) {
+        if (!(plugin instanceof com.sk89q.bukkit.migration.PermissionsProvider)) {
+            return null;
+        }
+
+        final com.sk89q.bukkit.migration.PermissionsProvider legacyPermissionsProvider = (com.sk89q.bukkit.migration.PermissionsProvider) plugin;
+        return new LegacyPermissionsProviderWrapper(legacyPermissionsProvider);
+    }
+
+    private LegacyPermissionsProviderWrapper(com.sk89q.bukkit.migration.PermissionsProvider legacyPermissionsProvider) {
+        this.legacyPermissionsProvider = legacyPermissionsProvider;
+    }
+
+    @Override
+    public boolean hasPermission(String name, String permission) {
+        return legacyPermissionsProvider.hasPermission(name, permission);
+    }
+
+    @Override
+    public boolean hasPermission(String worldName, String name, String permission) {
+        return legacyPermissionsProvider.hasPermission(worldName, name, permission);
+    }
+
+    @Override
+    public boolean inGroup(String player, String group) {
+        return legacyPermissionsProvider.inGroup(player, group);
+    }
+
+    @Override
+    public String[] getGroups(String player) {
+        return legacyPermissionsProvider.getGroups(player);
+    }
+
+    @Override
+    public boolean hasPermission(OfflinePlayer player, String permission) {
+        return legacyPermissionsProvider.hasPermission(player.getName(), permission);
+    }
+
+    @Override
+    public boolean hasPermission(String worldName, OfflinePlayer player, String permission) {
+        return legacyPermissionsProvider.hasPermission(worldName, player.getName(), permission);
+    }
+
+    @Override
+    public boolean inGroup(OfflinePlayer player, String group) {
+        return legacyPermissionsProvider.inGroup(player.getName(), group);
+    }
+
+    @Override
+    public String[] getGroups(OfflinePlayer player) {
+        return legacyPermissionsProvider.getGroups(player.getName());
+    }
+}