Implement latest rules prohibiting some self referencing typedefs.

runtime/vm/parser.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/parser.h"
 
 #include "vm/bigint_operations.h"
 #include "vm/class_finalizer.h"
 #include "vm/compiler.h"
 #include "vm/compiler_stats.h"
@@ skipping 2944 matching lines @@
     ErrorMsg(alias_name_pos,
              "'%s' is already defined", alias_name->ToCString());
   }
 
   // Create the function type alias, but share the signature function of the
   // canonical signature class.
   Class& function_type_alias = Class::Handle(
       Class::NewSignatureClass(*alias_name,
                                signature_function,
                                script_));
+  // This alias should not be marked as finalized yet, since it needs to be
+  // checked in the class finalizer for illegal self references.
+  ASSERT(!function_type_alias.IsCanonicalSignatureClass());
+  ASSERT(!function_type_alias.is_finalized());
   library_.AddClass(function_type_alias);
   ExpectSemicolon();
   pending_classes.Add(function_type_alias, Heap::kOld);
 }
 
 
 void Parser::ParseInterfaceDefinition(
     const GrowableObjectArray& pending_classes) {
   TRACE_PARSER("ParseInterfaceDefinition");
   const intptr_t interface_pos = token_index_;
@@ skipping 5466 matching lines @@
 void Parser::SkipQualIdent() {
   ASSERT(IsIdentifier());
   ConsumeToken();
   if (CurrentToken() == Token::kPERIOD) {
     ConsumeToken();  // Consume the kPERIOD token.
     ExpectIdentifier("identifier expected after '.'");
   }
 }
 
 }  // namespace dart