Introduce a new AccessorPair type for handling JavaScript accessors.

src/runtime.cc

Index: src/runtime.cc
diff --git a/src/runtime.cc b/src/runtime.cc
index 460132caa7968f470a63abf19a71c2b1ae761e65..ee5269e71dc7fa808c5d3534eb22facaadea83b6 100644
--- a/src/runtime.cc
+++ b/src/runtime.cc
@@ -1057,14 +1057,14 @@ RUNTIME_FUNCTION(MaybeObject*, Runtime_GetOwnProperty) {
         switch (details.type()) {
           case CALLBACKS: {
             // This is an accessor property with getter and/or setter.
-            FixedArray* callbacks =
-                FixedArray::cast(dictionary->ValueAt(entry));
+            AccessorPair* accessors =
+                AccessorPair::cast(dictionary->ValueAt(entry));
             elms->set(IS_ACCESSOR_INDEX, heap->true_value());
             if (CheckElementAccess(*obj, index, v8::ACCESS_GET)) {
-              elms->set(GETTER_INDEX, callbacks->get(0));
+              elms->set(GETTER_INDEX, accessors->getter());
             }
             if (CheckElementAccess(*obj, index, v8::ACCESS_SET)) {
-              elms->set(SETTER_INDEX, callbacks->get(1));
+              elms->set(SETTER_INDEX, accessors->setter());
             }
             break;
           }
@@ -1103,18 +1103,18 @@ RUNTIME_FUNCTION(MaybeObject*, Runtime_GetOwnProperty) {
   elms->set(CONFIGURABLE_INDEX, heap->ToBoolean(!result.IsDontDelete()));
 
   bool is_js_accessor = (result.type() == CALLBACKS) &&
-                        (result.GetCallbackObject()->IsFixedArray());
+                        (result.GetCallbackObject()->IsAccessorPair());
 
   if (is_js_accessor) {
     // __defineGetter__/__defineSetter__ callback.
     elms->set(IS_ACCESSOR_INDEX, heap->true_value());
 
-    FixedArray* structure = FixedArray::cast(result.GetCallbackObject());
+    AccessorPair* accessors = AccessorPair::cast(result.GetCallbackObject());
     if (CheckAccess(*obj, *name, &result, v8::ACCESS_GET)) {
-      elms->set(GETTER_INDEX, structure->get(0));
+      elms->set(GETTER_INDEX, accessors->getter());
     }
     if (CheckAccess(*obj, *name, &result, v8::ACCESS_SET)) {
-      elms->set(SETTER_INDEX, structure->get(1));
+      elms->set(SETTER_INDEX, accessors->setter());
     }
   } else {
     elms->set(IS_ACCESSOR_INDEX, heap->false_value());
@@ -10475,15 +10475,15 @@ RUNTIME_FUNCTION(MaybeObject*, Runtime_DebugGetPropertyDetails) {
       // If the callback object is a fixed array then it contains JavaScript
       // getter and/or setter.
       bool hasJavaScriptAccessors = result_type == CALLBACKS &&
-                                    result_callback_obj->IsFixedArray();
+                                    result_callback_obj->IsAccessorPair();
       Handle<FixedArray> details =
           isolate->factory()->NewFixedArray(hasJavaScriptAccessors ? 5 : 2);
       details->set(0, *value);
       details->set(1, property_details);
       if (hasJavaScriptAccessors) {
         details->set(2, isolate->heap()->ToBoolean(caught_exception));
-        details->set(3, FixedArray::cast(*result_callback_obj)->get(0));
-        details->set(4, FixedArray::cast(*result_callback_obj)->get(1));
+        details->set(3, AccessorPair::cast(*result_callback_obj)->getter());
+        details->set(4, AccessorPair::cast(*result_callback_obj)->setter());
       }
 
       return *isolate->factory()->NewJSArrayWithElements(details);