[JS IR] Adapt stepping tests for Kotlin/JS

compiler/testData/debug/stepping/class.kt

@@ -18,13 +18,13 @@ fun box() {
 // three to be hit both on entry to the constructor and on exit after storing the
 // value of prop.
 
-// EXPECTATIONS
+// EXPECTATIONS JVM JVM_IR
 // test.kt:12 box
 // test.kt:3 <init>
 // test.kt:4 <init>
 // EXPECTATIONS JVM_IR
 // test.kt:3 <init>
-// EXPECTATIONS
+// EXPECTATIONS JVM JVM_IR
 // test.kt:12 box
 // test.kt:13 box
 // test.kt:4 getProp
@@ -33,3 +33,8 @@ fun box() {
 // test.kt:7 foo
 // test.kt:8 foo
 // test.kt:15 box
+
+// EXPECTATIONS JS_IR
+// test.kt:12 box
+// test.kt:4 A
+// test.kt:14 box