KT-1747 Can't have main function in nested namespaces

#KT-1747 Fixed

js/js.tests/test/org/jetbrains/k2js/test/semantics/MiscTest.java

@@ -129,4 +129,8 @@ public final class MiscTest extends AbstractExpressionTest {
     public void testKt1865() throws Exception {
         checkFooBoxIsTrue("KT-1865.kt");
     }
+
+    public void testMainFunInNestedNamespace() throws Exception {
+        checkOutput("mainFunInNestedNamespace.kt", "ayee");
+    }
 }

js/js.translator/testFiles/expression/misc/cases/mainFunInNestedNamespace.kt

@@ -0,0 +1,7 @@
+package a.b.c
+
+import js.*
+
+fun main(args : Array<String>) {
+  println("ayee")
+}