[Serialization] Workaround registering static writeSelf method in metadata

`IrGeneratedDeclarationsRegistrar` assumes that all generated functions
  are correct from a Kotlin point of view. But `writeSelf` method on JVM
  is a static method outside any object/companion object

So to properly calculate containing class for this method we should
  generate a dispatch receiver parameter, register the method in metadata,
  and then remove the parameter (to make function static)

plugins/kotlinx-serialization/testData/boxIr/allConstructorsAccessible.kt

@@ -0,0 +1,19 @@
+// TARGET_BACKEND: JVM_IR
+// WITH_REFLECT
+
+import kotlinx.serialization.Serializable
+import kotlin.reflect.jvm.javaConstructor
+import kotlin.reflect.jvm.kotlinFunction
+
+@Serializable
+data class Tuple2<out A1, out A2>(
+    val _1: A1,
+    val _2: A2,
+)
+
+fun box(): String {
+    val cls = Tuple2::class
+    val ctor = cls.constructors.single { it.parameters.size == 4 }
+    val kf = ctor.javaConstructor?.kotlinFunction
+    return if (kf.toString() == "fun `<init>`(kotlin.Int, A1?, A2?, kotlinx.serialization.internal.SerializationConstructorMarker?): Tuple2<A1, A2>") "OK" else "Fail: $kf"
+}