JS: move more test to box tests

js/js.translator/testData/box/objectDeclaration/objectWithMethods.kt

@@ -0,0 +1,22 @@
+package foo
+
+class Test {
+    private val a = object {
+        fun c() = 3
+        fun b() = 2
+    }
+
+    fun doTest(): String {
+        if (a.c() != 3) {
+            return "fail1"
+        }
+        if (a.b() != 2) {
+            return "fail2"
+        }
+        return "OK"
+    }
+}
+
+fun box(): String {
+    return Test().doTest();
+}