Delegated members should not be synthetic

Otherwise they are invisible to Java code

compiler/testData/compileJavaAgainstKotlin/method/Delegation.java

@@ -0,0 +1,7 @@
+class JavaClass {
+    public static void main(String[] args) {
+        Test test = new Test();
+        test.foo();
+        test.getBar();
+    }
+}