Use an enum for indicating the component of an AccessorPair instead of a boolean flag.

src/runtime.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 4300 matching lines @@
 // There are 3 cases that lead here:
 // Step 4b - define a new accessor property.
 // Steps 9c & 12 - replace an existing data property with an accessor property.
 // Step 12 - update an existing accessor property with an accessor or generic
 //           descriptor.
 RUNTIME_FUNCTION(MaybeObject*, Runtime_DefineOrRedefineAccessorProperty) {
   ASSERT(args.length() == 5);
   HandleScope scope(isolate);
   CONVERT_ARG_HANDLE_CHECKED(JSObject, obj, 0);
   CONVERT_ARG_CHECKED(String, name, 1);
-  CONVERT_SMI_ARG_CHECKED(flag_setter, 2);
+  CONVERT_SMI_ARG_CHECKED(flag, 2);
   Object* fun = args[3];
   CONVERT_SMI_ARG_CHECKED(unchecked, 4);
 
   RUNTIME_ASSERT((unchecked & ~(READ_ONLY | DONT_ENUM | DONT_DELETE)) == 0);
   PropertyAttributes attr = static_cast<PropertyAttributes>(unchecked);
 
   RUNTIME_ASSERT(!obj->IsNull());
   RUNTIME_ASSERT(fun->IsSpecFunction() || fun->IsUndefined());
-  return obj->DefineAccessor(name, flag_setter == 0, fun, attr);
+  AccessorComponent component = flag == 0 ? ACCESSOR_GETTER : ACCESSOR_SETTER;
+  return obj->DefineAccessor(name, component, fun, attr);
 }
 
 // Implements part of 8.12.9 DefineOwnProperty.
 // There are 3 cases that lead here:
 // Step 4a - define a new data property.
 // Steps 9b & 12 - replace an existing accessor property with a data property.
 // Step 12 - update an existing data property with a data or generic
 //           descriptor.
 RUNTIME_FUNCTION(MaybeObject*, Runtime_DefineOrRedefineDataProperty) {
   ASSERT(args.length() == 4);
@@ skipping 5944 matching lines @@
     return *isolate->factory()->NewJSArrayWithElements(single_interval);
   }
 }
 
 
 RUNTIME_FUNCTION(MaybeObject*, Runtime_LookupAccessor) {
   ASSERT(args.length() == 3);
   CONVERT_ARG_CHECKED(JSObject, obj, 0);
   CONVERT_ARG_CHECKED(String, name, 1);
   CONVERT_SMI_ARG_CHECKED(flag, 2);
-  return obj->LookupAccessor(name, flag == 0);
+  AccessorComponent component = flag == 0 ? ACCESSOR_GETTER : ACCESSOR_SETTER;
+  return obj->LookupAccessor(name, component);
 }
 
 
 #ifdef ENABLE_DEBUGGER_SUPPORT
 RUNTIME_FUNCTION(MaybeObject*, Runtime_DebugBreak) {
   ASSERT(args.length() == 0);
   return Execution::DebugBreakHelper();
 }
 
 
@@ skipping 3315 matching lines @@
     // Handle last resort GC and make sure to allow future allocations
     // to grow the heap without causing GCs (if possible).
     isolate->counters()->gc_last_resort_from_js()->Increment();
     isolate->heap()->CollectAllGarbage(Heap::kNoGCFlags,
                                        "Runtime::PerformGC");
   }
 }
 
 
 } }  // namespace v8::internal