CI lazy methods: re-explore array types with different element types

Previously upon encountering a second array this would truncate the search for
available types, but since they may have different element types this could lead
to missing the availability of one or more of the element classes. Now we search
array::reference every time we encounter it.

src/java_bytecode/ci_lazy_methods.cpp

@@ -344,7 +344,10 @@ void ci_lazy_methodst::initialize_needed_classes_from_pointer(
   const symbol_typet &class_type=to_symbol_type(pointer_type.subtype());
   const auto &param_classid=class_type.get_identifier();
 
-  if(needed_lazy_methods.add_needed_class(param_classid))
+  // Note here: different arrays may have different element types, so we should
+  // explore again even if we've seen this classid before in the array case.
+  if(needed_lazy_methods.add_needed_class(param_classid) ||
+     is_java_array_tag(param_classid))
   {
     gather_field_types(pointer_type.subtype(), ns, needed_lazy_methods);
   }