Promote KClass.cast/safeCast, KAnnotatedElement.hasAnnotation() to stable

libraries/stdlib/src/kotlin/reflect/KClasses.kt

@@ -19,8 +19,8 @@ import kotlin.internal.LowPriorityInOverloadResolution
  * @see [KClass.isInstance]
  * @see [KClass.safeCast]
  */
-@SinceKotlin("1.3")
-@ExperimentalStdlibApi
+@SinceKotlin("1.4")
+@WasExperimental(ExperimentalStdlibApi::class)
 @LowPriorityInOverloadResolution
 fun <T : Any> KClass<T>.cast(value: Any?): T {
     if (!isInstance(value)) throw ClassCastException("Value cannot be cast to $qualifiedOrSimpleName")
@@ -39,8 +39,8 @@ internal expect val KClass<*>.qualifiedOrSimpleName: String?
  * @see [KClass.isInstance]
  * @see [KClass.cast]
  */
-@SinceKotlin("1.3")
-@ExperimentalStdlibApi
+@SinceKotlin("1.4")
+@WasExperimental(ExperimentalStdlibApi::class)
 @LowPriorityInOverloadResolution
 fun <T : Any> KClass<T>.safeCast(value: Any?): T? {
     return if (isInstance(value)) value as T else null