Use the return value of vm native methods to set the return value,

vm/native_entry.h

Index: vm/native_entry.h
===================================================================
--- vm/native_entry.h	(revision 11528)
+++ vm/native_entry.h	(working copy)
@@ -24,17 +24,13 @@
 typedef void (*NativeFunction)(NativeArguments* arguments);
 
 
-#define NATIVE_ENTRY_FUNCTION(name) DN_##name
+#define NATIVE_ENTRY_FUNCTION(name) BootstrapNatives::DN_##name
 
 
-// Helper macros for declaring and defining native entries.
-#define REGISTER_NATIVE_ENTRY(name, count)                                     \
-  { ""#name, NATIVE_ENTRY_FUNCTION(name), count },
-
-
 #define DEFINE_NATIVE_ENTRY(name, argument_count)                              \
-  static void DN_Helper##name(Isolate* isolate, NativeArguments* arguments);   \
-  void NATIVE_ENTRY_FUNCTION(name)(Dart_NativeArguments args) {                \
+  static RawObject* DN_Helper##name(Isolate* isolate,                          \
+                                    NativeArguments* arguments);               \
+  void NATIVE_ENTRY_FUNCTION(name)(Dart_NativeArguments args) {         \
     CHECK_STACK_ALIGNMENT;                                                     \
     VERIFY_ON_TRANSITION;                                                      \
     NativeArguments* arguments = reinterpret_cast<NativeArguments*>(args);     \
@@ -43,16 +39,15 @@
     {                                                                          \
       Zone zone(arguments->isolate());                                         \
       HANDLESCOPE(arguments->isolate());                                       \
-      DN_Helper##name(arguments->isolate(), arguments);                        \
+      arguments->SetReturnUnsafe(                                              \
+          DN_Helper##name(arguments->isolate(), arguments));                   \
     }                                                                          \
     VERIFY_ON_TRANSITION;                                                      \
   }                                                                            \
-  static void DN_Helper##name(Isolate* isolate, NativeArguments* arguments)
+  static RawObject* DN_Helper##name(Isolate* isolate,                          \
+                                    NativeArguments* arguments)
 
 
-#define DECLARE_NATIVE_ENTRY(name, argument_count)                             \
-  extern void NATIVE_ENTRY_FUNCTION(name)(Dart_NativeArguments arguments);
-
 // Natives should throw an exception if an illegal argument is passed.
 // type name = value.
 #define GET_NATIVE_ARGUMENT(type, name, value)                                 \