Cleanups based on Kevin's and Florian's suggestions.

runtime/vm/code_generator.h

 // 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.
 
 #ifndef VM_CODE_GENERATOR_H_
 #define VM_CODE_GENERATOR_H_
 
 #include "vm/globals.h"
 #include "vm/runtime_entry.h"
 
 namespace dart {
 
-class ArgumentsDescriptor;
+class Array;
 template <typename T> class GrowableArray;
 class ICData;
 class Instance;
 
 // Declaration of runtime entries called from stub or generated code.
 DECLARE_RUNTIME_ENTRY(AllocateArray);
 DECLARE_RUNTIME_ENTRY(AllocateClosure);
 DECLARE_RUNTIME_ENTRY(AllocateImplicitInstanceClosure);
 DECLARE_RUNTIME_ENTRY(AllocateImplicitStaticClosure);
 DECLARE_RUNTIME_ENTRY(AllocateContext);
@@ skipping 56 matching lines @@
 #undef DEFINE_ENUM_LIST
 };
 
 
 const char* DeoptReasonToText(intptr_t deopt_id);
 
 
 RawCode* ResolveCompileInstanceCallTarget(
     const Instance& receiver,
     const ICData& ic_data,
-    const ArgumentsDescriptor& arguments_descriptor);
+    const Array& arguments_descriptor);
 
 void DeoptimizeAll();
 void DeoptimizeIfOwner(const GrowableArray<intptr_t>& classes);
 
 }  // namespace dart
 
 #endif  // VM_CODE_GENERATOR_H_