Fix several bugs in serialization of inner generic classes

- Interner was working incorrectly with parents
- nested classes were serialized in codegen out of any context

 #KT-5660 Fixed

compiler/backend/src/org/jetbrains/jet/codegen/ImplementationBodyCodegen.java

@@ -232,7 +232,8 @@ public class ImplementationBodyCodegen extends ClassBodyCodegen {
 
         if (state.getClassBuilderMode() != ClassBuilderMode.FULL) return;
 
-        DescriptorSerializer serializer = new DescriptorSerializer(new JavaSerializerExtension(v.getSerializationBindings()));
+        DescriptorSerializer serializer =
+                DescriptorSerializer.create(descriptor, new JavaSerializerExtension(v.getSerializationBindings()));
 
         ProtoBuf.Class classProto = serializer.classProto(descriptor).build();
 

compiler/backend/src/org/jetbrains/jet/codegen/PackageCodegen.java

@@ -272,7 +272,7 @@ public class PackageCodegen {
             if (file.isScript()) return;
         }
 
-        DescriptorSerializer serializer = new DescriptorSerializer(new JavaSerializerExtension(bindings));
+        DescriptorSerializer serializer = DescriptorSerializer.createTopLevel(new JavaSerializerExtension(bindings));
         Collection<PackageFragmentDescriptor> packageFragments = Lists.newArrayList();
         ContainerUtil.addIfNotNull(packageFragments, packageFragment);
         ContainerUtil.addIfNotNull(packageFragments, compiledPackageFragment);