[K/JS] Add support of compilation with ES-classes

compiler/testData/debug/stepping/functionCallWithDefault.kt

@@ -24,5 +24,5 @@ inline fun bar(i: Int = 1) {
 
 // EXPECTATIONS JS_IR
 // test.kt:4 box
-// test.kt:8 foo
+// test.kt:9 foo
 // test.kt:6 box

compiler/testData/debug/stepping/simpleDefaultArg.kt

@@ -17,5 +17,4 @@ fun box(): String {
 // test.kt:8 box
 
 // EXPECTATIONS JS_IR
-// test.kt:8 box
-// test.kt:3 ifoo
+// test.kt:8 box

compiler/testData/debug/stepping/simpleDefaultArgWithInline.kt

@@ -27,5 +27,4 @@ fun box(): String {
 
 // EXPECTATIONS JS_IR
 // test.kt:5 box
-// test.kt:14 box
-// test.kt:8 ifoo2
+// test.kt:14 box