JS backend: remove ECMA 3, but several tests is broken.

Main reason: overload extention property:

Int.bar = 1
String.bar = 2

libraries/tools/kotlin-js-tests/src/test/web/index.html

@@ -6,7 +6,7 @@
 	<link rel="stylesheet" href="qunit.css">
 	<script src="qunit.js"></script>
 
-    <script src="../../../../../../dist/kotlinc/lib/kotlinEcma3.js"></script>
+    <script src="../../../../../../dist/kotlinc/lib/kotlin.js"></script>
     <script src="../../../target/js/kotlin-js-tests.js"></script>
 
     <script src="deepEqual.js"></script>