[K/JS] Support companion objects in external and exported declarations

js/js.translator/testData/box/jsQualifier/interfacesWithCompanion.kt

@@ -0,0 +1,31 @@
+// TARGET_BACKEND: JS_IR
+// TARGET_BACKEND: JS_IR_ES6
+// EXPECTED_REACHABLE_NODES: 1238
+// FILE: bar.kt
+@file:JsQualifier("bar")
+package bar
+
+external interface Bar {
+    companion object {
+        fun ok(): String
+    }
+}
+
+// FILE: test.kt
+import bar.Bar
+
+fun box(): String {
+    return Bar.ok()
+}
+
+// FILE: test.js
+var bar = function() {
+    var Bar = {
+        ok() {
+            return "OK"
+        }
+    };
+    return {
+        Bar: Bar
+    }
+}();