backend/tests: Add blackbox tests from Kotlin JVM

Added tests from testData/codegen/box directory. There are blackbox tests
in other directories and they are to be added.

backend.native/tests/external/codegen/blackbox/reflection/mapping/jvmStatic/companionObjectFunction.kt

@@ -0,0 +1,38 @@
+// TODO: muted automatically, investigate should it be ran for JS or not
+// IGNORE_BACKEND: JS
+
+// WITH_REFLECT
+
+import kotlin.reflect.KFunction
+import kotlin.reflect.jvm.*
+import kotlin.test.*
+
+class C {
+    companion object {
+        @JvmStatic
+        fun foo(s: String): Int = s.length
+    }
+}
+
+fun box(): String {
+    val foo = C.Companion::class.members.single { it.name == "foo" } as KFunction<*>
+
+    val j = foo.javaMethod ?: return "Fail: no Java method found for C::foo"
+    assertEquals(3, j.invoke(C, "abc"))
+
+    val k = j.kotlinFunction ?: return "Fail: no Kotlin function found for Java method C::foo"
+    assertEquals(3, k.call(C, "def"))
+
+
+    val staticMethod = C::class.java.getDeclaredMethod("foo", String::class.java)
+    val k2 = staticMethod.kotlinFunction ?:
+             return "Fail: no Kotlin function found for static bridge for @JvmStatic method in companion object C::foo"
+    assertEquals(3, k2.call(C, "ghi"))
+
+    assertFailsWith(NullPointerException::class) { k2.call(null, "")!! }
+
+    val j2 = k2.javaMethod
+    assertEquals(j, j2)
+
+    return "OK"
+}

backend.native/tests/external/codegen/blackbox/reflection/mapping/jvmStatic/objectFunction.kt

@@ -0,0 +1,25 @@
+// TODO: muted automatically, investigate should it be ran for JS or not
+// IGNORE_BACKEND: JS
+
+// WITH_REFLECT
+
+import kotlin.reflect.KFunction
+import kotlin.reflect.jvm.*
+import kotlin.test.assertEquals
+
+object O {
+    @JvmStatic
+    fun foo(s: String): Int = s.length
+}
+
+fun box(): String {
+    val foo = O::class.members.single { it.name == "foo" } as KFunction<*>
+
+    val j = foo.javaMethod ?: return "Fail: no Java method found for O::foo"
+    assertEquals(3, j.invoke(null, "abc"))
+
+    val k = j.kotlinFunction ?: return "Fail: no Kotlin function found for Java method O::foo"
+    assertEquals(3, k.call(O, "def"))
+
+    return "OK"
+}