Revert of [runtime] Introduce maps for the likely cases of FromPropertyDescriptor.

src/property-descriptor.cc

Index: src/property-descriptor.cc
diff --git a/src/property-descriptor.cc b/src/property-descriptor.cc
index 750f948adbe399263ce44f194e82d9d3d8ffde6c..243a9faac3a76cd33f1d5563cb065b5b5e34c772 100644
--- a/src/property-descriptor.cc
+++ b/src/property-descriptor.cc
@@ -12,8 +12,6 @@
 
 namespace v8 {
 namespace internal {
-
-namespace {
 
 // Helper function for ToPropertyDescriptor. Comments describe steps for
 // "enumerable", other properties are handled the same way.
@@ -103,14 +101,12 @@
 }
 
 
-void CreateDataProperty(Isolate* isolate, Handle<JSObject> object,
-                        Handle<String> name, Handle<Object> value) {
+static void CreateDataProperty(Isolate* isolate, Handle<JSObject> object,
+                               Handle<String> name, Handle<Object> value) {
   LookupIterator it(object, name, LookupIterator::OWN_SKIP_INTERCEPTOR);
   Maybe<bool> result = JSObject::CreateDataProperty(&it, value);
   CHECK(result.IsJust() && result.FromJust());
 }
-
-}  // namespace
 
 
 // ES6 6.2.4.4 "FromPropertyDescriptor"
@@ -118,36 +114,6 @@
   DCHECK(!(PropertyDescriptor::IsAccessorDescriptor(this) &&
            PropertyDescriptor::IsDataDescriptor(this)));
   Factory* factory = isolate->factory();
-  if (IsRegularAccessorProperty()) {
-    // Fast case for regular accessor properties.
-    Handle<JSObject> result = factory->NewJSObjectFromMap(
-        isolate->accessor_property_descriptor_map());
-    result->InObjectPropertyAtPut(JSAccessorPropertyDescriptor::kGetIndex,
-                                  *get());
-    result->InObjectPropertyAtPut(JSAccessorPropertyDescriptor::kSetIndex,
-                                  *set());
-    result->InObjectPropertyAtPut(
-        JSAccessorPropertyDescriptor::kEnumerableIndex,
-        isolate->heap()->ToBoolean(enumerable()));
-    result->InObjectPropertyAtPut(
-        JSAccessorPropertyDescriptor::kConfigurableIndex,
-        isolate->heap()->ToBoolean(configurable()));
-    return result;
-  }
-  if (IsRegularDataProperty()) {
-    // Fast case for regular data properties.
-    Handle<JSObject> result =
-        factory->NewJSObjectFromMap(isolate->data_property_descriptor_map());
-    result->InObjectPropertyAtPut(JSDataPropertyDescriptor::kValueIndex,
-                                  *value());
-    result->InObjectPropertyAtPut(JSDataPropertyDescriptor::kWritableIndex,
-                                  isolate->heap()->ToBoolean(writable()));
-    result->InObjectPropertyAtPut(JSDataPropertyDescriptor::kEnumerableIndex,
-                                  isolate->heap()->ToBoolean(enumerable()));
-    result->InObjectPropertyAtPut(JSDataPropertyDescriptor::kConfigurableIndex,
-                                  isolate->heap()->ToBoolean(configurable()));
-    return result;
-  }
   Handle<JSObject> result = factory->NewJSObject(isolate->object_function());
   if (has_value()) {
     CreateDataProperty(isolate, result, factory->value_string(), value());