[JS IR BE] Fix private field names

compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/utils/SimpleNameGenerator.kt

@@ -135,6 +135,7 @@ class SimpleNameGenerator : NameGenerator {
                     } else {
                         nameBuilder.append('.')
                         nameBuilder.append(getNameForDeclaration(declaration.parent as IrDeclaration, context))
+                        if (declaration.visibility == Visibilities.PRIVATE) nameDeclarator = context.currentScope::declareFreshName
                     }
                 }
                 is IrClass -> {

compiler/testData/codegen/box/closures/captureExtensionReceiver.kt

@@ -1,4 +1,3 @@
-// IGNORE_BACKEND: JS_IR
 interface  B<T> {
     val bar: T
 }

compiler/testData/codegen/box/localClasses/inLocalExtensionFunction.kt

@@ -1,4 +1,3 @@
-// IGNORE_BACKEND: JS_IR
 package test
 
 class C(val s : String) {

compiler/testData/codegen/box/localClasses/inLocalExtensionProperty.kt

@@ -1,4 +1,3 @@
-// IGNORE_BACKEND: JS_IR
 package test
 
 class C(val s : String) {

compiler/testData/codegen/box/localClasses/localClassCaptureExtensionReceiver.kt

@@ -1,4 +1,3 @@
-// IGNORE_BACKEND: JS_IR
 class Outer {
     val foo = "Foo"
 

compiler/testData/codegen/box/operatorConventions/kt14201_2.kt

@@ -1,4 +1,3 @@
-// IGNORE_BACKEND: JS_IR
 class A {
     val z: String = "OK"
 }