quick migration changes for refresh(ish) support; ref pterodactyl#2875

This still fails in a 2017 migration, but I don't care.

Author: DaneEveritt

database/migrations/2019_03_02_151321_fix_unique_index_to_account_for_host.php

@@ -30,6 +30,8 @@ public function up()
     public function down()
     {
         Schema::table('databases', function (Blueprint $table) {
+            $table->dropForeign(['database_host_id']);
+
             $table->dropUnique(['database_host_id', 'database']);
             $table->dropUnique(['database_host_id', 'username']);
 

database/migrations/2020_03_22_163911_merge_permissions_table_into_subusers.php

@@ -108,7 +108,8 @@ public function down()
         foreach (DB::select('SELECT id, permissions FROM subusers') as $datum) {
             $values = [];
             foreach (json_decode($datum->permissions, true) as $permission) {
-                if (! empty($v = $flipped[$permission])) {
+                $v = $flipped[$permission] ?? null;
+                if (! empty($v)) {
                     $values[] = $datum->id;
                     $values[] = $v;
                 }