add test for generating annotations on the setter of a delegated property; (KT-4169); properly generate backing field for delegated property with a setter

compiler/testData/codegen/boxWithStdlib/annotations/delegatedPropertySetter.kt

@@ -0,0 +1,27 @@
+import java.lang.annotation.*
+
+Retention(RetentionPolicy.RUNTIME)
+annotation class First
+
+class MyClass() {
+    public var x: String by Delegate()
+        [First] set
+}
+
+class Delegate {
+    fun get(t: Any?, p: PropertyMetadata): String {
+        return "OK"
+    }
+
+    fun set(t: Any?, p: PropertyMetadata, i: String) {}
+}
+
+fun box(): String {
+    val e = javaClass<MyClass>()
+
+    val e1 = e.getDeclaredMethod("setX", javaClass<String>()).getAnnotations()
+    if (e1.size() != 1) return "Fail E1 size: ${e1.toList()}"
+    if (e1[0].annotationType() != javaClass<First>()) return "Fail: ${e1.toList()}"
+
+    return MyClass().x
+}