Loosen the signature of declaringJavaClass to accept Enum<E> instead of E

KT-54005

libraries/stdlib/jvm/runtime/kotlin/jvm/JvmClassMapping.kt

@@ -114,5 +114,5 @@ public val <T : Annotation> T.annotationClass: KClass<out T>
  */
 @SinceKotlin("1.7")
 @InlineOnly
-public inline val <E : Enum<E>> E.declaringJavaClass: Class<E>
+public inline val <E : Enum<E>> Enum<E>.declaringJavaClass: Class<E>
     get() = (this as java.lang.Enum<E>).declaringClass

libraries/stdlib/jvm/test/enums/EnumDeclaringJavaClassTest.kt

@@ -43,4 +43,12 @@ class EnumDeclaringJavaClassTest {
         set.addAll(TestEnum.E.declaringJavaClass.enumConstants.toList())
         assertEquals(EnumSet.of(TestEnum.E), set)
     }
+
+    @Test
+    fun worksOnGenericEnum() {
+        fun <T : Enum<T>> check(e: Enum<T>) {
+            assertEquals<Class<*>>(e.declaringJavaClass, TestEnum::class.java)
+        }
+        check(TestEnum.E)
+    }
 }