classlib: add TSystem#getSecurityManager()TSecurityManager and an empty implementation of TSecurityManager

classlib/src/main/java/org/teavm/classlib/java/lang/TSecurityManager.java

@@ -0,0 +1,24 @@
+/*
+ *  Copyright 2022 ulugbek.abdullaev.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+package org.teavm.classlib.java.lang;
+
+// Note: this class is left empty on purpose -
+//  functionality is intended to be added as need arises
+public class TSecurityManager {
+
+    public TSecurityManager() {
+    }
+}

classlib/src/main/java/org/teavm/classlib/java/lang/TSystem.java

@@ -75,6 +75,10 @@ public final class TSystem extends TObject {
         return null;
     }
 
+    public static TSecurityManager getSecurityManager() {
+        return new TSecurityManager();
+    }
+
     public static void arraycopy(TObject src, int srcPos, TObject dest, int destPos, int length) {
         if (src == null || dest == null) {
             throw new TNullPointerException("Either src or dest is null");