Support synthetic accessors for @JvmDefault members

compiler/testData/codegen/java8/box/jvm8/defaults/privateInDefaultImpls.kt

@@ -0,0 +1,23 @@
+// !API_VERSION: 1.3
+// JVM_TARGET: 1.8
+// WITH_RUNTIME
+
+interface Test {
+    @kotlin.annotations.JvmDefault
+    fun test(): String {
+        return privateFun() + privateProp
+    }
+
+    private fun privateFun(): String {
+        return "O"
+    }
+
+    private val privateProp: String
+        get() = "K"
+}
+
+class TestImpl: Test
+
+fun box(): String {
+    return TestImpl().test()
+}