KT-23397 Optimize out field for property delegate when it's safe (JVM)

compiler/testData/codegen/box/delegatedProperty/delegateToSingleton/delegateToEnumInAClass.kt

@@ -0,0 +1,17 @@
+// WITH_STDLIB
+// CHECK_BYTECODE_LISTING
+
+enum class E {
+    OK, NOT_OK
+}
+
+class C {
+    val s: String by E.OK
+}
+
+val c = C()
+
+operator fun E.getValue(thisRef: Any?, property: Any?): String =
+    if (this == E.OK && thisRef == c) "OK" else "Failed"
+
+fun box(): String = c.s