JS backend: added more tests for closures.

js/js.translator/testData/closure/cases/closureThisInFunctionWhichNamedSameAsParentClass.kt

@@ -0,0 +1,19 @@
+package foo
+
+class B(val b: String)
+
+class A(val a: String) {
+    fun B.A() = { a + b }
+
+    fun foo(a: B) = a.A()()
+}
+
+fun box(): String {
+    val bar = A("bar")
+    val baz = B("baz")
+
+    val r = bar.foo(baz)
+    if (r != "barbaz") return "$r";
+
+    return "OK"
+}