Serialize descriptors for local/anonymous classes on JVM

Reflection needs this information to work for local classes and anonymous
objects

compiler/testData/serialization/local/localClassInSignature.kt

@@ -0,0 +1,13 @@
+// CLASS_NAME_SUFFIX: $main$Local
+
+fun main() {
+    open class Local {
+        fun param(l: Local) {}
+
+        val returnType: Local = this
+
+        fun Local.receiver() = this
+
+        fun <T : Local, U : T> generic(t: T): U = null!!
+    }
+}