Merge boxWithJava testData into box, delete BoxWithJava test

compiler/testData/codegen/box/statics/hidePrivateByPublic.kt

@@ -0,0 +1,30 @@
+// FILE: Child.java
+
+class Child extends Parent {
+    public static String a = "2";
+    public static String foo() {
+        return "Child.foo()";
+    }
+    public static String foo(int i) {
+        return "Child.foo(int)";
+    }
+}
+
+// FILE: Parent.java
+
+class Parent {
+    private static int a = 1;
+    private static String foo() {
+        return "Parent.foo";
+    }
+}
+
+// FILE: test.kt
+
+fun box(): String {
+    if (Child.a != "2") return "Fail #1"
+    if (Child.foo() != "Child.foo()") return "Fail #2"
+    if (Child.foo(1) != "Child.foo(int)") return "Fail #3"
+
+    return "OK"
+}