NJ2K: preserve annotations while converting class to object

#KT-38879 fixed

nj2k/src/org/jetbrains/kotlin/nj2k/conversions/ClassToObjectPromotionConversion.kt

@@ -49,7 +49,7 @@ class ClassToObjectPromotionConversion(context: NewJ2kConverterContext) : Recurs
                                 it is JKClass && it.classKind != JKClass.ClassKind.COMPANION
                             }.map { it.detached(element.classBody) }
                         },
-                        JKAnnotationList(),
+                        element.annotationList,
                         element.otherModifierElements,
                         element.visibilityElement,
                         JKModalityModifierElement(Modality.FINAL)

nj2k/testData/newJ2k/class/classToObjectWithAnnotations.java

@@ -0,0 +1,6 @@
+@interface Foo
+
+@Foo
+class A {
+    static void bar() {}
+}

nj2k/testData/newJ2k/class/classToObjectWithAnnotations.kt

@@ -0,0 +1,6 @@
+internal annotation class Foo
+
+@Foo
+internal object A {
+    fun bar() {}
+}

nj2k/tests/org/jetbrains/kotlin/nj2k/NewJavaToKotlinConverterSingleFileTestGenerated.java

@@ -839,6 +839,11 @@ public class NewJavaToKotlinConverterSingleFileTestGenerated extends AbstractNew
             runTest("nj2k/testData/newJ2k/class/ClassShadowing.java");
         }
 
+        @TestMetadata("classToObjectWithAnnotations.java")
+        public void testClassToObjectWithAnnotations() throws Exception {
+            runTest("nj2k/testData/newJ2k/class/classToObjectWithAnnotations.java");
+        }
+
         @TestMetadata("classWithEmptyMethods.java")
         public void testClassWithEmptyMethods() throws Exception {
             runTest("nj2k/testData/newJ2k/class/classWithEmptyMethods.java");