Test for KT-9712 (fixed along with KT-9717)

#KT-9712 Fixed

compiler/testData/codegen/boxWithStdlib/delegatedProperty/kt9712.kt

@@ -0,0 +1,22 @@
+import kotlin.properties.Delegates
+
+object X {
+    public var O: String
+        by Delegates.observable("O") { prop, old, new -> }
+        private set
+}
+
+open class A {
+    public var K: String
+        by Delegates.observable("") { prop, old, new -> }
+        protected set
+}
+
+class B : A() {
+    init {
+        K = "K"
+    }
+}
+
+fun box(): String =
+        X.O + B().K

compiler/tests/org/jetbrains/kotlin/codegen/generated/BlackBoxWithStdlibCodegenTestGenerated.java

@@ -1468,6 +1468,12 @@ public class BlackBoxWithStdlibCodegenTestGenerated extends AbstractBlackBoxCode
             doTestWithStdlib(fileName);
         }
 
+        @TestMetadata("kt9712.kt")
+        public void testKt9712() throws Exception {
+            String fileName = JetTestUtils.navigationMetadata("compiler/testData/codegen/boxWithStdlib/delegatedProperty/kt9712.kt");
+            doTestWithStdlib(fileName);
+        }
+
         @TestMetadata("stackOverflowOnCallFromGetValue.kt")
         public void testStackOverflowOnCallFromGetValue() throws Exception {
             String fileName = JetTestUtils.navigationMetadata("compiler/testData/codegen/boxWithStdlib/delegatedProperty/stackOverflowOnCallFromGetValue.kt");