Fixed boxing of SuccessOrFailure inside SafeContinuation impl

libraries/stdlib/coroutines/jvm/src/kotlin/coroutines/SafeContinuationJvm.kt

@@ -36,7 +36,7 @@ internal actual constructor(
         while (true) { // lock-free loop
             val cur = this.result // atomic read
             when {
-                cur === UNDECIDED -> if (RESULT.compareAndSet(this, UNDECIDED, result)) return
+                cur === UNDECIDED -> if (RESULT.compareAndSet(this, UNDECIDED, result._value)) return
                 cur === COROUTINE_SUSPENDED -> if (RESULT.compareAndSet(this, COROUTINE_SUSPENDED, RESUMED)) {
                     delegate.resumeWith(result)
                     return

libraries/stdlib/coroutines/src/kotlin/SuccessOrFailure.kt

@@ -19,7 +19,7 @@ import kotlin.internal.InlineOnly
 import kotlin.jvm.JvmField
 
 @SinceKotlin("1.3")
-public inline class SuccessOrFailure<out T> @PublishedApi internal constructor(private val _value: Any?) {
+public inline class SuccessOrFailure<out T> @PublishedApi internal constructor(internal val _value: Any?) {
     // discovery
 
     public val isSuccess: Boolean get() = _value !is Failure