Add some tests for kotlinx.serialization plugin:

- declaration checker
- bytecode listings
- JVM IR

Improve @Transient redundant reporting

plugins/kotlin-serialization/kotlin-serialization-compiler/testData/diagnostics/NonSerializable.kt

@@ -0,0 +1,17 @@
+// !DIAGNOSTICS: -UNUSED_PARAMETER,-UNUSED_VARIABLE
+
+// FILE: test.kt
+import kotlinx.serialization.*
+
+class NonSerializable
+
+@Serializable
+class Basic(val foo: <!PLUGIN_ERROR("Serializer has not been found for type 'NonSerializable'. To use context serializer as fallback, explicitly annotate type or property with @ContextualSerialization")!>NonSerializable<!>)
+
+@Serializable
+class Inside(val foo: List<<!PLUGIN_ERROR("Serializer has not been found for type 'NonSerializable'. To use context serializer as fallback, explicitly annotate type or property with @ContextualSerialization")!>NonSerializable<!>>)
+
+@Serializable
+class WithImplicitType {
+    <!PLUGIN_ERROR("Serializer has not been found for type 'NonSerializable'. To use context serializer as fallback, explicitly annotate type or property with @ContextualSerialization")!>val foo = NonSerializable()<!>
+}