Use comment directive for not generated case to be valid Java file

compiler/tests-common/tests/org/jetbrains/kotlin/asJava/LightClassTestCommon.kt

@@ -16,12 +16,13 @@ import java.util.regex.Pattern
 
 object LightClassTestCommon {
     private val SUBJECT_FQ_NAME_PATTERN = Pattern.compile("^//\\s*(.*)$", Pattern.MULTILINE)
+    private const val NOT_GENERATED_DIRECTIVE = "// NOT_GENERATED"
 
     fun testLightClass(
-            expectedFile: File,
-            testDataFile: File,
-            findLightClass: (String) -> PsiClass?,
-            normalizeText: (String) -> String
+        expectedFile: File,
+        testDataFile: File,
+        findLightClass: (String) -> PsiClass?,
+        normalizeText: (String) -> String
     ) {
         val text = FileUtil.loadFile(testDataFile, true)
         val matcher = SUBJECT_FQ_NAME_PATTERN.matcher(text)
@@ -36,7 +37,7 @@ object LightClassTestCommon {
 
     private fun actualText(fqName: String?, lightClass: PsiClass?, normalizeText: (String) -> String): String {
         if (lightClass == null) {
-            return "<not generated>"
+            return NOT_GENERATED_DIRECTIVE
         }
         TestCase.assertTrue("Not a light class: $lightClass ($fqName)", lightClass is KtLightClass)
 
@@ -52,5 +53,5 @@ object LightClassTestCommon {
     // Actual text for light class is generated with ClsElementImpl.appendMirrorText() that can find empty DefaultImpl inner class in stubs
     // for all interfaces. This inner class can't be used in Java as it generally is not seen from light classes built from Kotlin sources.
     // It is also omitted during classes generation in backend so it also absent in light classes built from compiled code.
-    fun removeEmptyDefaultImpls(text: String) : String = text.replace("\n    static final class DefaultImpls {\n    }\n", "")
+    fun removeEmptyDefaultImpls(text: String): String = text.replace("\n    static final class DefaultImpls {\n    }\n", "")
 }