Cleanup some handle creation code, was showing up in the CompileAll testing that we are doing with …

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/flags.h"
 
 #ifndef DART_PRECOMPILED_RUNTIME
 
 #include "lib/invocation_mirror.h"
@@ skipping 11814 matching lines @@
                 Error::Handle(Z),  // No previous error.
                 script_,
                 type->token_pos(),
                 "type parameter '%s' cannot be referenced "
                 "from static member",
                 String::Handle(Z, type_parameter.name()).ToCString());
             return;
           }
           // A type parameter cannot be parameterized, so make the type
           // malformed if type arguments have previously been parsed.
-          if (!TypeArguments::Handle(Z, type->arguments()).IsNull()) {
+          if (type->arguments() != TypeArguments::null()) {
             *type = ClassFinalizer::NewFinalizedMalformedType(
                 Error::Handle(Z),  // No previous error.
                 script_,
                 type_parameter.token_pos(),
                 "type parameter '%s' cannot be parameterized",
                 String::Handle(Z, type_parameter.name()).ToCString());
             return;
           }
           *type = type_parameter.raw();
           return;
@@ skipping 20 matching lines @@
       ClassFinalizer::FinalizeMalformedType(
           Error::Handle(Z),  // No previous error.
           script_,
           parameterized_type,
           "type '%s' is not loaded",
           String::Handle(Z, parameterized_type.UserVisibleName()).ToCString());
       return;
     }
   }
   // Resolve type arguments, if any.
-  const TypeArguments& arguments = TypeArguments::Handle(Z, type->arguments());
-  if (!arguments.IsNull()) {
+  if (type->arguments() != TypeArguments::null()) {
+    const TypeArguments& arguments =
+        TypeArguments::Handle(Z, type->arguments());
     const intptr_t num_arguments = arguments.Length();
+    AbstractType& type_argument = AbstractType::Handle(Z);
     for (intptr_t i = 0; i < num_arguments; i++) {
-      AbstractType& type_argument = AbstractType::Handle(Z,
-                                                         arguments.TypeAt(i));
+      type_argument ^= arguments.TypeAt(i);
       ResolveTypeFromClass(scope_class, finalization, &type_argument);
       arguments.SetTypeAt(i, type_argument);
     }
   }
 }
 
 
 LocalVariable* Parser::LookupLocalScope(const String& ident) {
   if (current_block_ == NULL) {
     return NULL;
@@ skipping 2581 matching lines @@
     const ArgumentListNode& function_args,
     const LocalVariable* temp_for_last_arg,
     bool is_super_invocation) {
   UNREACHABLE();
   return NULL;
 }
 
 }  // namespace dart
 
 #endif  // DART_PRECOMPILED_RUNTIME