Address review comments in commited cl (issue 10460002).

runtime/vm/code_generator_ia32.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/globals.h"  // Needed here to get TARGET_ARCH_IA32.
 #if defined(TARGET_ARCH_IA32)
 
 #include "vm/code_generator.h"
 
 #include "lib/error.h"
@@ skipping 799 matching lines @@
 
   // The function type of a closure may have type arguments. In that case, pass
   // the type arguments of the instantiator.
   const Class& cls = Class::Handle(function.signature_class());
   ASSERT(!cls.IsNull());
   const bool requires_type_arguments = cls.HasTypeArguments();
   if (requires_type_arguments) {
     ASSERT(!function.IsImplicitStaticClosureFunction());
     const bool kPushInstantiator = false;
     GenerateInstantiatorTypeArguments(node->token_index(), kPushInstantiator);
+  } else {
+    const Immediate raw_null =
+        Immediate(reinterpret_cast<intptr_t>(Object::null()));
+    __ pushl(raw_null);  // No type arguments.
   }
   const Code& stub = Code::Handle(
       StubCode::GetAllocationStubForClosure(function));
   const ExternalLabel label(function.ToCString(), stub.EntryPoint());
   GenerateCall(node->token_index(), &label, PcDescriptors::kOther);
-  if (requires_type_arguments) {
-    __ popl(ECX);  // Pop type arguments.
-  }
+  __ popl(ECX);  // Pop type arguments.
   if (function.IsImplicitInstanceClosureFunction()) {
     __ popl(ECX);  // Pop receiver.
   }
   if (IsResultNeeded(node)) {
     __ pushl(EAX);
   }
 }
 
 
 void CodeGenerator::VisitPrimaryNode(PrimaryNode* node) {
@@ skipping 2133 matching lines @@
   const Error& error = Error::Handle(
       Parser::FormatError(script, token_index, "Error", format, args));
   va_end(args);
   Isolate::Current()->long_jump_base()->Jump(1, error);
   UNREACHABLE();
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_IA32