[es6] Implement default parameters

src/bootstrapper.cc

Index: src/bootstrapper.cc
diff --git a/src/bootstrapper.cc b/src/bootstrapper.cc
index 36d322bb354dc7c790ba87f5fffbbecfd8204525..cbc7d7b8547dd8719a46f0b6870a0275cd1e2d2c 100644
--- a/src/bootstrapper.cc
+++ b/src/bootstrapper.cc
@@ -1843,6 +1843,7 @@ EMPTY_NATIVE_FUNCTIONS_FOR_FEATURE(harmony_sloppy)
 EMPTY_NATIVE_FUNCTIONS_FOR_FEATURE(harmony_sloppy_let)
 EMPTY_NATIVE_FUNCTIONS_FOR_FEATURE(harmony_unicode_regexps)
 EMPTY_NATIVE_FUNCTIONS_FOR_FEATURE(harmony_rest_parameters)
+EMPTY_NATIVE_FUNCTIONS_FOR_FEATURE(harmony_default_parameters)
 EMPTY_NATIVE_FUNCTIONS_FOR_FEATURE(harmony_reflect)
 EMPTY_NATIVE_FUNCTIONS_FOR_FEATURE(harmony_spreadcalls)
 EMPTY_NATIVE_FUNCTIONS_FOR_FEATURE(harmony_destructuring)
@@ -1878,6 +1879,7 @@ EMPTY_INITIALIZE_GLOBAL_FOR_FEATURE(harmony_proxies)
 EMPTY_INITIALIZE_GLOBAL_FOR_FEATURE(harmony_sloppy)
 EMPTY_INITIALIZE_GLOBAL_FOR_FEATURE(harmony_sloppy_let)
 EMPTY_INITIALIZE_GLOBAL_FOR_FEATURE(harmony_rest_parameters)
+EMPTY_INITIALIZE_GLOBAL_FOR_FEATURE(harmony_default_parameters)
 EMPTY_INITIALIZE_GLOBAL_FOR_FEATURE(harmony_spreadcalls)
 EMPTY_INITIALIZE_GLOBAL_FOR_FEATURE(harmony_destructuring)
 EMPTY_INITIALIZE_GLOBAL_FOR_FEATURE(harmony_object)
@@ -2561,6 +2563,7 @@ bool Genesis::InstallExperimentalNatives() {
   static const char* harmony_sloppy_let_natives[] = {nullptr};
   static const char* harmony_unicode_regexps_natives[] = {nullptr};
   static const char* harmony_rest_parameters_natives[] = {nullptr};
+  static const char* harmony_default_parameters_natives[] = {nullptr};
   static const char* harmony_reflect_natives[] = {"native harmony-reflect.js",
                                                   nullptr};
   static const char* harmony_spreadcalls_natives[] = {