Implement handling of arrow functions in the parser

src/factory.cc

Index: src/factory.cc
diff --git a/src/factory.cc b/src/factory.cc
index 3aacc59d503673d627955e79d590acb3a1f066bb..a6704f364820afd3e33c7225e7fab9960fd3c345 100644
--- a/src/factory.cc
+++ b/src/factory.cc
@@ -1788,11 +1788,13 @@ Handle<SharedFunctionInfo> Factory::NewSharedFunctionInfo(
     Handle<String> name,
     int number_of_literals,
     bool is_generator,
+    bool is_arrow,
     Handle<Code> code,
     Handle<ScopeInfo> scope_info) {
   Handle<SharedFunctionInfo> shared = NewSharedFunctionInfo(name);
   shared->set_code(*code);
   shared->set_scope_info(*scope_info);
+  shared->set_is_arrow(is_arrow);
   int literals_array_size = number_of_literals;
   // If the function contains object, regexp or array literals,
   // allocate extra space for a literals array prefix containing the
@@ -1990,7 +1992,7 @@ void Factory::InitializeFunction(Handle<JSFunction> function,
 static Handle<Map> MapForNewFunction(Isolate* isolate,
                                      Handle<SharedFunctionInfo> function_info,
                                      MaybeHandle<Object> maybe_prototype) {
-  if (maybe_prototype.is_null()) {
+  if (maybe_prototype.is_null() || function_info->is_arrow()) {
     return function_info->strict_mode() == SLOPPY
         ? isolate->sloppy_function_without_prototype_map()
         : isolate->strict_function_without_prototype_map();