[K/JS] Rework main function call to support it in per-file

js/js.translator/testData/box/esModules/main/differentMains.kt

@@ -0,0 +1,24 @@
+// EXPECTED_REACHABLE_NODES: 1281
+// ES_MODULES
+// CALL_MAIN
+
+var ok: String = "OK"
+
+fun main(args: Array<Int>) {
+    ok += "Fail Int"
+}
+
+fun main(args: Array<in String>) {
+    ok += "Fail IN"
+}
+
+fun main(args: Array<String>): Unit? {
+    ok += "Fail return Unit?"
+    return Unit
+}
+
+fun Any.main(args: Array<String>) {
+    ok += "Fail Any.main(...)"
+}
+
+fun box() = ok