[es6] Partially implement Reflect.set.

src/bootstrapper.cc

Index: src/bootstrapper.cc
diff --git a/src/bootstrapper.cc b/src/bootstrapper.cc
index 0b63ceb8f980bd336b027ba46b5c067a656a19d6..2c49b3d21f1135d73a9e14f600e0a5e50d0396e1 100644
--- a/src/bootstrapper.cc
+++ b/src/bootstrapper.cc
@@ -2203,6 +2203,8 @@ void Genesis::InitializeGlobal_harmony_reflect() {
                         Builtins::kReflectIsExtensible, 1, true);
   SimpleInstallFunction(reflect, "preventExtensions",
                         Builtins::kReflectPreventExtensions, 1, true);
+  SimpleInstallFunction(reflect, "set",
+                        Builtins::kReflectSet, 3, false);
   SimpleInstallFunction(reflect, "setPrototypeOf",
                         Builtins::kReflectSetPrototypeOf, 2, true);
 }