[K/JS] Generate tests for K2 + ES-classes compilation

compiler/testData/codegen/box/multiplatform/defaultArguments/superCall.kt

@@ -5,7 +5,7 @@
 // IGNORE_BACKEND: NATIVE
 // IGNORE_BACKEND: JVM_IR
 // IGNORE_BACKEND: JVM
-// IGNORE_BACKEND_K2: JS_IR
+// IGNORE_BACKEND_K2: JS_IR, JS_IR_ES6
 
 // FILE: lib.kt
 

compiler/testData/codegen/box/multiplatform/k2/basic/transitiveSuperclassActualization.kt

@@ -1,6 +1,6 @@
 // IGNORE_BACKEND_K1: ANY
 //   IGNORE_REASON: new rules for supertypes matching are implemented only in K2
-// IGNORE_BACKEND_K2: JS_IR, WASM
+// IGNORE_BACKEND_K2: JS_IR, JS_IR_ES6, WASM
 //   IGNORE_REASON: `JsName` in js.translator/testData/_commonFiles/testUtils.kt is invisible for some reason
 // LANGUAGE: +MultiPlatformProjects
 // ISSUE: KT-59356

compiler/testData/codegen/box/multiplatform/k2/basic/widerVisibilityInActualClassifier.kt

@@ -1,6 +1,6 @@
 // IGNORE_BACKEND_K1: ANY
 //   IGNORE_REASON: KT-59355 is fixed only in K2
-// IGNORE_BACKEND_K2: JS_IR, WASM
+// IGNORE_BACKEND_K2: JS_IR, JS_IR_ES6, WASM
 //   IGNORE_REASON: `JsName` in js.translator/testData/_commonFiles/testUtils.kt is invisible for some reason
 // LANGUAGE: +MultiPlatformProjects
 // ISSUE: KT-59355

compiler/testData/codegen/box/multiplatform/k2/migratedOldTests/mpp_default_args.kt

@@ -7,7 +7,7 @@
 // IGNORE_BACKEND_K1: ANY
 
 // IllegalArgumentException: arg wrongly != this@Test5: arg=null, this@Test5=[object Object]
-// IGNORE_BACKEND_K2: JS_IR
+// IGNORE_BACKEND_K2: JS_IR, JS_IR_ES6
 // Wrong box result 'arg1 wrongly != this@Test5: arg1=Inner@1346131020, this@Test5=Test5@314569418'; Expected "OK"
 // IGNORE_BACKEND_K2: WASM