Fix equality of implicit closures in the Dart VM.

runtime/vm/object.cc

Index: runtime/vm/object.cc
===================================================================
--- runtime/vm/object.cc	(revision 25920)
+++ runtime/vm/object.cc	(working copy)
@@ -1847,9 +1847,9 @@
   invocation.SetNumOptionalParameters(desc.NamedCount(),
                                       false);  // Not positional.
   invocation.set_parameter_types(Array::Handle(Array::New(desc.Count(),
-                                                         Heap::kOld)));
+                                                          Heap::kOld)));
   invocation.set_parameter_names(Array::Handle(Array::New(desc.Count(),
-                                                         Heap::kOld)));
+                                                          Heap::kOld)));
   // Receiver.
   invocation.SetParameterTypeAt(0, Type::Handle(Type::DynamicType()));
   invocation.SetParameterNameAt(0, Symbols::This());
@@ -2082,19 +2082,13 @@
                                    const Script& script,
                                    intptr_t token_pos) {
   const Class& result = Class::Handle(New(name, script, token_pos));
-  const Type& super_type = Type::Handle(Type::ObjectType());
-  ASSERT(!super_type.IsNull());
   // Instances of a signature class can only be closures.
   result.set_instance_size(Closure::InstanceSize());
   result.set_next_field_offset(Closure::InstanceSize());
-  result.set_super_type(super_type);
+  // Signature classes extend the DartFunction class.
+  result.set_super_type(Type::Handle(Type::Function()));
   result.set_is_synthesized_class();
   result.set_type_arguments_field_offset(Closure::type_arguments_offset());
-  // Implements interface "Function".
-  const Type& function_type = Type::Handle(Type::Function());
-  const Array& interfaces = Array::Handle(Array::New(1, Heap::kOld));
-  interfaces.SetAt(0, function_type);
-  result.set_interfaces(interfaces);
   if (!signature_function.IsNull()) {
     result.PatchSignatureFunction(signature_function);
   }