Move final parts of class literal setup into a single runtime call

src/full-codegen/x64/full-codegen-x64.cc

Index: src/full-codegen/x64/full-codegen-x64.cc
diff --git a/src/full-codegen/x64/full-codegen-x64.cc b/src/full-codegen/x64/full-codegen-x64.cc
index 894a64a2ee657f5c23b9b79ddaad84cf1febc17d..775e188310e3ff2c9e424436c60229668c13e58a 100644
--- a/src/full-codegen/x64/full-codegen-x64.cc
+++ b/src/full-codegen/x64/full-codegen-x64.cc
@@ -2478,24 +2478,12 @@ void FullCodeGenerator::EmitClassDefineProperties(ClassLiteral* lit,
     }
   }
 
-  // prototype
-  __ CallRuntime(Runtime::kToFastProperties, 1);
-
-  // constructor
-  __ CallRuntime(Runtime::kToFastProperties, 1);
-
-  if (is_strong(language_mode())) {
-    __ movp(scratch,
-            FieldOperand(rax, JSFunction::kPrototypeOrInitialMapOffset));
-    __ Push(rax);
-    __ Push(scratch);
-    // TODO(conradw): It would be more efficient to define the properties with
-    // the right attributes the first time round.
-    // Freeze the prototype.
-    __ CallRuntime(Runtime::kObjectFreeze, 1);
-    // Freeze the constructor.
-    __ CallRuntime(Runtime::kObjectFreeze, 1);
-  }
+  // Set both the prototype and constructor to have fast properties, and also
+  // freeze them in strong mode.
+  __ CallRuntime(is_strong(language_mode())
+                     ? Runtime::kFinalizeClassDefinitionStrong
+                     : Runtime::kFinalizeClassDefinition,
+                 2);
 }