JS: refactor translation of callable references to top-level properties

js/js.translator/testData/box/callableReference/property/topLevelVar.kt

@@ -4,6 +4,9 @@ var x = 1
 
 val y = 2
 
+val z: Int
+    get() = 3
+
 fun box(): String {
     var refX = ::x
     assertEquals(1, refX.get())
@@ -16,5 +19,9 @@ fun box(): String {
     assertEquals(2, refY.get())
     assertEquals("y", refY.name)
 
+    var refZ = ::z
+    assertEquals(3, refZ.get())
+    assertEquals("z", refZ.name)
+
     return "OK"
 }