Enable ES6 unscopables

src/bootstrapper.cc

Index: src/bootstrapper.cc
diff --git a/src/bootstrapper.cc b/src/bootstrapper.cc
index a3b37421bb043b53ad12903175b92eba90da1b11..4d2bf955f48f4692aecdcb004e6c71feab100940 100644
--- a/src/bootstrapper.cc
+++ b/src/bootstrapper.cc
@@ -1592,6 +1592,7 @@ void Genesis::InstallNativeFunctions() {
                  native_object_notifier_perform_change);
 
   INSTALL_NATIVE(Symbol, "symbolIterator", iterator_symbol);
+  INSTALL_NATIVE(Symbol, "symbolUnscopables", unscopables_symbol);
 
   INSTALL_NATIVE_MATH(abs)
   INSTALL_NATIVE_MATH(acos)
@@ -1622,10 +1623,6 @@ void Genesis::InstallExperimentalNativeFunctions() {
     INSTALL_NATIVE(JSFunction, "DerivedSetTrap", derived_set_trap);
     INSTALL_NATIVE(JSFunction, "ProxyEnumerate", proxy_enumerate);
   }
-
-  if (FLAG_harmony_unscopables) {
-    INSTALL_NATIVE(Symbol, "symbolUnscopables", unscopables_symbol);
-  }
 }
 
 #undef INSTALL_NATIVE
@@ -2062,7 +2059,6 @@ bool Genesis::InstallExperimentalNatives() {
     INSTALL_EXPERIMENTAL_NATIVE(i, generators, "generator.js")
     INSTALL_EXPERIMENTAL_NATIVE(i, strings, "harmony-string.js")
     INSTALL_EXPERIMENTAL_NATIVE(i, arrays, "harmony-array.js")
-    INSTALL_EXPERIMENTAL_NATIVE(i, unscopables, "unscopables.js")
   }
 
   InstallExperimentalNativeFunctions();